''Marine Boy'' (Japanese: ''Undersea Boy Marine'') is a 1965 anime series starring Marine Boy, an agent for the Ocean Patrol. It's the job of the Ocean Patrol to, well, [[ExactlyWhatItSaysOnTheTin patrol the ocean]].

When it was first run in the US in 1967, it was simply presented as a children's cartoon, not as a product from Japan, thus some people consider it a "stealth" anime series. In any case, this made it one of the [[GatewaySeries first anime series seen by many people]], even if they weren't familiar with the term "anime."

Not to be confused with a [[ChildSoldier boy Marine]].

!!This anime provides examples of:

* AbnormalAmmo: Ocean Patrol Submarines usually carry small torpedoes, but they can also fire boxing-glove torpedoes, nets, drills, and others.
* AllAnimalsAreDogs: Splasher has some dog-like qualities, most notably Marine Boy calls him with a dolphin whistle.
* ArtificialGill: Professor Fumble's inventions: "oxy-gum" which Marine Boy can chew and receive hours of oxygenation.
* BadassAdorable:
** Marine Boy is very young but very capable and athletic.
** Neptina is even younger and often winds up saving Marine Boy.
* DepartmentOfRedundancyDepartment: One episode is titled "The Power of Power".
* GodivaHair: How Neptina usually stays decent (a technique also used in the Japanese animated version of Hans Christian Andersen's The Little Mermaid).
* ImposterForgotOneDetail: A false Marine Boy calls the real one's Dad by a variation of "father" the real Marine Boy doesn't use and this clues Marine Boy's Dad to the fact someone is impersonating him.
* ImprobableAge: Marine Boy is essentially an underwater policeman and he's presumably somewhere around 13 years old.
* LoyalAnimalCompanion: Splasher, a white dolphin who accompanies Marine Boy.
* PrecisionGuidedBoomerang: Marine Boy's weapon of choice. It folds up and can electrify targets to boot.
* SceneryCensor: Mermaid Neptina wears nothing; her breasts are concealed by [[GodivaHair her long hair]] or the scenery.
* SpeaksFluentAnimal: Neptina speaks with Splasher often.
* SuperNotDrowningSkills: Done through Professor Fumble's inventions and the fact Neptina is a mermaid.
* UnscaledMerfolk: Neptina is half-dolphin instead of half-fish.