The Smart Guy who serves as a complete opposite character of Nobita.
- Academic Athlete: The smartest kid in the school, but also athletic and good at sports.
- The Ace: Smart, nice, athletic, popular, etc. Ace is even his name in the DisneyXD dub.
- Adaptational Attractiveness: To make his Chick Magnet status more justified, he's more handsome in the 2005 anime compared to his character design in the 1979 anime
- Agent Scully: Dekisugi has shown a tendency to thinking through reasoning and rationality. In short; he didn't believe in superstitions and regards them to be "scientifically explainable". That said, he actually had a debate with Nobita about Magic in the original version of 'Great Adventure into the Underworld'.
- Always Someone Better: His appearance seems to be used to show how much of a loser Nobita is.
- Beauty Equals Goodness: He's much better-looking than the main boys Nobita, Gian, and Suneo. He's also much nicer than them and a better person than them in every way.
- Berserk Button: He absolutely hates when others pick on Nobita, sometimes trying to defend him, once he even yelled at Gian for that reason. Which leads to the following trope...
- Beware the Nice Ones: There are moments where he can get angry, though they happen less often than Shizuka.
- Birds of a Feather: Pretty much a male Shizuka, and the reason why he gets along so well with her.
- Bishōnen: His face is drawn in the exact same way as Shizuka, the only difference being their hairstyle and his lack of eyelashes.
- Book Smart: He always gets perfect grades and the teacher constantly praises him.
- Broken Ace: Rarely, but there are times when even he needs Doraemon's help.
- In one episode, he's threatened by an older kid outside of school.
- In another episode, he's terrorized by anonymous telephone calls in the middle of the night, and this makes him so nervous that he starts getting (slightly) lower grades than his usual perfect scores. It turns out that another jealous Always Second Best student was prank calling him to terrorize him.
- Chick Magnet: He is considered good-looking by many girls in his class.
- Child Prodigy: An academically brilliant and multi-talented kid. Although his favorites are Astronomy and Philosophy, he excels at every subject.
- Chronic Hero Syndrome: He always tries to help others, but there are times when he gets a bit so insistent about that and overdoes it. This leads to Heroic Fatigue in 'The Three Dimensional Puzzle Hammer'; where he insists on solving every puzzle that Nobita and Suneo left around town, mainly because they were objects that other people wanted/needed to use, by the end he's so exhausted that he collapses at the mere sight of another puzzle.
- Did Not Get the Girl: In Stand by Me Doraemon, his future self mentions (while Drowning My Sorrows) that he has proposed to Shizuka, but she told him that he could manage without her, unlike Nobita. That said, he makes an effort to encourage Nobita to make Shizuka happy the day before their wedding day and expresses little to no jealousy.
- Fan of Underdog: In 'The Perfect Love Letter' he ends up wanting to emulate Nobita at everything, including going with him to and being tardy for school, after being impressed by Nobita's writing skills, courtesy of an automated pen. He assumed, after a brief shock, that acting like Nobita will help him to improve his writing.
- Fatal Flaw: Both his earnestness to help others and Scully-tendencies, on separate occasions led to him having a breakdown due to fatigue or being unable to rationally explain something.
- He's basically everything Nobita isn't. It doesn't help that they both have similar character design.
- Like Suneo, he's intelligent and possesses many talents. However, Suneo is considerably meaner (or at least gives off a meaner demeanor) than Dekisugi, who never brags about anything unlike Suneo. And while Nobita is jealous of both of them, Suneo is more intentionally antagonistic towards Nobita than Dekisugi.
- Friendly Enemy: Could be regarded (in the extremes) as this in terms of his relationship with Nobita, though the enmity is always one-sided on Nobita's part, and Dekisugi treats him like a friend.
- Gentleman and a Scholar: Despite his intelligence and many talents, he never shows off about it. He's always very humble, and genuinely friendly and respectful to everyone, including Nobita.
- Hero Antagonist: He's a perfectly nice guy who just happens to be often antagonized by the main character because he sees him as a romantic rival.
- Iconic Sequel Character: Dekisugi never appeared in the 1973 anime because his character wasn't added until later in the manga.
- Irony: He's known by everyone to be incredibly intelligent, but is more often than not left confused by Nobita's behavior or Doraemon's gadgets.
- Last-Name Basis: Dekisugi is his last name.
- Meaningful Name: "Dekisugi" literally means "overachiever". His dub name "Ace Goody" also counts.
- Nice Guy: The nicest character in the series, always willing to help out. Even Shizuka can be a little snippy at times, but Dekisugi is polite to everyone all the time and almost never gets angry.
- Oblivious to Hatred: He thinks Nobita is a friendly classmate, and is completely unaware of Nobita's hatred and jealousy towards him, despite all the obvious signs. It helps that Nobita can actually be friendly and supportive towards him on occasion.
- Odd Name Out: Just like Suneo, he has rather odd-sounding name in the english dub.
- Parody Sue: He's more the embodiment of the "perfect human being" rather than a real character. He's The Ace at absolutely everything, he has zero personality flaws, and even his very, very rare Not So Above It All moments are mostly limited to getting justifiably angry or being a bit of a pushover.
- Renaissance Man: He's an Academic Athlete, other than artistic, good at drawing, a Supreme Chef etc.
- The Rival: Nobita rival for Shizuka's affection. Unfortunately for Nobita, Shizuka tends to prefer the company of him; who is more of her intellectual equal. This stimulates Nobita into connoting bizarre schemes, with the help of Doraemon's gadgets to keep them apart.
- The Sixth Ranger: Sometimes. It's not rare for him to receive calls by his friends, asking for guidance or tips. Due to his Parody Sue status, however, he rarely gets into the thick of things like the other kids. Notably more so in the anime, where his role is usually to be the Infodump.
- Skilled, but Naïve: He's intelligent and excels at everything, but is unaware of Nobita's jealousy towards him.
- A Taste of Defeat: A rather unintentional example. The aforementioned 'Puzzle Hammer' story; not only he postponed a planned activity with Shizuka to solve all those puzzles due to Nobita and Suneo's shenanigans at turning everything into puzzle pieces, but recruited her into helping him with the task. They eventually become so mentally fatigued, when Nobita asked for their help to rebuild Suneo who accidentally turned into puzzle pieces, they just quickly passed out and lying on the floor, much to the former's confusion.
The unnamed Sensei is Nobita's teacher.
- A Day in the Limelight: An episode is about the possibilty of him leaving the school. Nobita and the other students persuade him to stay.
- Everyone Calls Him "Barkeep": He's only called "sensei" ("teacher") in the Japanese version, and he's only called "sir" in the Hindi dub.
- Jerk with a Heart of Gold: He is usually strict with his students, especially Nobita and Gian (both problematic students in their own ways). However, he also frequently expresses his concern and hope for his students and wants them to become better individuals in the future.
- No Name Given: His real name is unknown and he is only referred to as "Sensei", but in the NTV anime, his name is given as Ganari.
- Reasonable Authority Figure: He's strict, but well-respected by his students for being this. He even managed to inspire Nobita occasionally.
- Satellite Character: Most of his appearances are about him teaching at school as well as coming back from work at school.
- Stern Teacher: He is a strict teacher who often punishes Nobita for failing his tests, being late to school, or forgetting his homework which range from standing in the hallway to sweeping the classroom after-school. The Running Gag is extended to the point that as Nobita, simply meeting the Teacher in the streets, usually during holidays, will have Nobita admonished for his lack of school performance.
- Two-Teacher School: He's apparently the only teacher in the school. He's the math teacher (they hardly ever mention other subjects), who is also seen teaching gym, the cooking classes, and all the other school activities.
Haruo and Yasuo
Two recurring friends of the gang.
- Adaptation Name Change: In the 1979 anime, Yasuo was known as Yamada and Haruo as Masashi Noda.
- Everyone Has Standards: They don't appreciate Gian's bullying and dreadful singing more than everyone else.
- Extreme Doormat: To Gian, like everyone. He ocassionally bullies them and steals their belongings when Nobita is not around and they never attempt to do something about it.
- Fat and Skinny: Haruo is the fat one while Yasuo is thin.
- Flat Character: They mostly appear as background players in the baseball games, or among the group of kids terrorized by Gian. They never have A Day in the Limelight, and are rarely addressed by name. Sometimes they are credited as "Boy A" and "Boy B".
- Kids Are Cruel: Downplayed, but sometimes they join Gian and Suneo when they pick on Nobita. On their own, they are pretty harmless though.
- Nice Hat: Yasuo is always wearing a cap.
- Pet the Dog: They occasionally have concerned looks on their faces when Gian beats up Nobita.
- Those Two Guys: Usually seen together.
- A Day in the Limelight: The manga chapter 'Tracer Badges' and its 1979 adaptation is this for him, it even reveals his name. Not longer the case in the last series.
- Establishing Character Moment: His main role serves to show that he is a kind and forgiving boy.
- Megane: He wears glasses and looks cute.
- Nice Guy: He never makes fun of/bullies Nobita. Consider the event of his debut story.
- Recurring Extra: The classic anime drops him out after his main story and his model only appears in the background. The new anime reduces his role in that episode; but keeps him around, sometimes with a speaking role, in others.
- Turn the Other Cheek: Despite Nobita using the Tracer Badges to get him into trouble with his mom; he stil refuses to join Gian, Suneo and the others into setting a trap to ambush Nobita.
- Berserk Button: It's understandable he would get angry, but he blows up every time the baseball hits his home's windows or his pottery collection.
- Jerk with a Heart of Gold: While he's mostly seen as grumpy and in a bad mood, he can be very friendly on occasion, much to the boys' surprise.
- Punny Name: His name is a pun on the word thunder in Japanese.
Appear in only one chapter so far. Dekisugi's father.
A beautiful scientist that Dekisugi will marry in the future. Has a son with him named Hideyo.
Dekisugi's prodigy son. Nobisuke Jr.'s friend.
Tsubasa Ito (Sera Ivy)
A lovely singer and popstar of the gang and friends. She sometimes appear in public.
- Continuity Nod: She is the adult version of the girl in Paa-man, another Fujiko works. In one of the stories she kept the picture of Mitsuo, the Paa-Man himself, in her necklace.
- Adapted Out: Only appears in early chapters and the 1973 anime. She was scrapped from appearing in future manga episodes and the 1979 anime series due to Fujiko F. Fujio loathing her.
- The Bus Came Back: She appeared as a cameo in one episode from the 2005 series
- Spell My Name with an "S": Is it Gachako or Gatchako?
A robot green dog and Doraemon's best friend.