- Awesome Music: The title theme by Nancy Sinatra (known by many of the young ones through Robbie Williams' "Millennium").
- Complete Monster: Ernst Stavro Blofeld, head of SPECTRE note and James Bond's Arch-Enemy, is an icy sociopath interested only in what profits him. Running SPECTRE with an iron fist, Blofeld facilitates terrorism around the world and any underling who fails dies a painful, ignominious end. When he and Bond finally come face to face, Blofeld is attempting to start a nuclear war to have the Soviets and the Americans wipe one another out, allowing SPECTRE to blackmail the newest superpowers.
- Fair for Its Day: Even though the film features some general Asian stereotypes, like Osato saying "Ah, so..." while chatting with Bond, Bond's allies in the Japanese Secret Service are all very competent and helpful.
- Franchise Original Sin: Most of the wackier elements of the franchise — such as the more cartoonish villains and over-the-top sets — that have been widely ridiculed in the years since got their start here. The next film actually toned it down, but after that met with an underwhelming reception, Connery's brief comeback and then the majority of Roger Moore's era would go full-tilt on these elements.
- Hilarious in Hindsight:
- The title and its abbreviation, YOLT, became pretty amusing when the saying "You Only Live Once", abbreviated as "YOLO", became subject to Memetic Mutation in 2012, even spawning something of a Fandom Rivalry from Bond fans.
- Donald Pleasence, after playing Blofeld, would go on to play Michael Myers' Arch-Enemy in the Halloween films, Dr. Loomis. Of course, an actor with the same name as Myers' would go on to play Blofeld parody Dr. Evil in the Austin Powers franchise.
- Ho Yay: Of a sort. Bond's password to meet his contact in Japan is "I love you", which leads to the following exchange:
Bond: If you're Tanaka, then how do you feel about me?Tanaka: I... love you.Bond: I'm glad we've got that out of the way.
- Blofeld has to peek around his bodyguard Hans to show his face to Bond and the audience.
- Bond's "Japanese" disguise makes him look more like Spock.
- Narm Charm: Blofeld as the bald, scarred man with a white cat has been referenced and parodied so many times (and is so over-the-top anyway) it can be difficult to take him seriously nowadays. However, the reason why it's been parodied so often is precisely because it's an extremely striking portrayal, and the creepiness of Pleasance's performance makes it easy to see why it became iconic.
- One-Scene Wonder: After he reveals himself to Bond, Blofeld is only in a couple of scenes, yet he manages to be one of the most memorable villains in any Bond film.
- Retroactive Recognition:
- As Charles Gray would go on to play Blofeld in Diamonds Are Forever, it can be pretty jarring to see him as a One-Scene Wonder here if the viewer has seen the later film first.
- The Giant Mook Bond fights in Osato Industries has gained this since it has come out that he was the grandfather of a certain Dwayne Johnson.
- "Seinfeld" Is Unfunny: You Only Live Twice was the one of the first, if not the first, time a villain used a secret volcano lair. It's a concept that has been used (and parodied) so often that modern viewers might find it trite.
- Special Effects Failure:
- The majority of the budget was funelled into the admittedly impressive volcano set, meaning that the rocket model effects ended up being rather short-changed.
- Relating to the volcano, while the actual set is quite impressive, the optical compositing effects used for establishing shots of the volcano are very obvious, especially on the Blu-Ray edition. Similar compositing issues plague some shots in the film's outer-space Cold Open, while other shots in the same sequence qualify as Visual Effects of Awesome.
- Bond goes undercover as a Japanese peasant. Sean Connery in pancake makeup is one of the series' more embarrassing moments.
- Stock Footage Failure: The Russian space launch uses stock footage of an American Gemini launch, down to the palm trees in the foreground.
- Values Dissonance: 'In Japan, men come first, women come second.' It's really hard to not sound like a dick repeating that line in the 21st century, isn't it?
- Unless you're using it in the Austin Powers sense.
- What An Idiot: If Spectre hadn't sent an assassin to kill Henderson while he was talking to James Bond, Bond wouldn't have been able to find the clue that led him to the exact island where Blofeld had his base. In turn, the clue was documentation that a tourist had been killed due to her photographing a ship. If they hadn't killed her and documented it, Bond wouldn't have known where to look for the base. And thirdly, when Bond looks for the base, he doesn't find anything, but when four helicopters try to kill him, he knows he's in the right place.
- It Was His Sled: Dr. Shatterhand is Blofeld.