Oolong's initial appearance was as a villain who terrorized a village and kidnapped their young women. Unfortunately for him, the young women were quite comfortable being stolen and living in wealth and he never found the "nice shy girl" he was looking for. Son Goku defeated Oolong and the girls were returned to their village. Bulma decided that he might be useful on her Dragonball quest and persuaded him to join their expedition. He does have his moments. At first Oolong tries to take the Dragonballs for himself, but he eats a "sweetrot" (a play on sweetarts) that causes him to have diarrhea (the trots), anytime someone whistles "Sweee!" (a phrase used to call pigs in for feeding time), which Bulma often uses against him in the first saga.

Eventually he becomes good friends with Goku and the others, and helps them to find more Dragonballs. In the Emperor Pilaf Saga, Oolong realizes that Pilaf's plan to wish himself world domination can be ruined by making a wish first as the dragon can only grant one wish. In the manga and the original Japanese anime, Oolong asks for a pair of panties just before Pilaf finishes. In the English anime, Oolong asks for the most comfortable underwear in the world, but inadvertently gets female underwear. With this action, Oolong literally saved the world, or as he put it, his "good deed for the day". For a time, he wears said underwear on his head, evidently proud of the gift Shenlong gave him.

The perverted pig appears every so often in Dragonball, helping out the gang when he can. After Dragon Ball, Oolong was kept around primarily for comic relief. His poor shapeshifting skills (and innate cowardice) made him a very weak character that didn't have much to do once the tone was shifted to more serious action.

In Dragon Ball Z, his character dwindles to little importance, although in the anime and several movies, he appears quite often as comic relief. In the Saiyan Saga he asks Shenlong if he can kill the Saiyans instead of reviving Goku, but Shenlong says he can't do that. At the Kame House he watches the battle against the Saiyans from television, and later with Uranai Baba's Crystal Ball.

In the Freeza Saga, Oolong, Muten Roshi, Puar, Yajirobe and Chi-Chi try to go to Namek with Dr. Briefs' ship, but to Oolong's delight, their ship breaks down before takeoff. In the Garlic Jr. Saga, Oolong, along with everyone else at the Kame House, is affected with Garlic Jr.'s mist, but is later cured. In the Android Saga, Oolong stays at the Kame House with the others, waiting from news of their friends. In a rare moment of compassion he cries out when Pu'ar faints, their rivalry long forgotten.


In the Buu Saga, Oolong is at the 25th Tenka'ichi Budokai supporting his friends and later goes with Bulma and the others look for the Dragonballs. In the same day he is turned into chocolate and eaten by Majin Buu, but as with everyone else, he is wished back to life and later gives his powers to Goku's Genki Dama (Spirit Bomb). At the end of the series, Oolong is at the 28th Tenka'ichi Budokai, once again supporting his friends. Unlike many of the characters, he hasn't aged at all.

Oolong makes a Cameo appearance in Dragon Ball GT, in episode 40, "Piccolo's Decision". In Dragon Ball GT, Oolong's wish for panties leads to the creation of Liu Xing Long (Oceanus Shenlong).