Oo! Oo! Oolong! (ウーロンあらわる！！ Ūron Arawaru!!, lit. "Oolong Appears!!") is the fifth chapter of the Dragon Ball manga.
The cover features Bulma wearing a military uniform and standing in front of an airplane, while Goku is standing behind, curiously looking at it. The cigarette in Bulma's mouth was removed for the Kanzenban edition.
While arriving at the deserted town with Bulma, Goku claims to sense the presence of people around. When trying to find them, he punches open the door to the house of Sherman Priest, only to him come out bring an axe down on his head. The axe shatters when hitting Goku's hard head, frightening both the Sherman Priest and Bulma. Sherman Priest first seems to think Goku is the shapeshifting demon named Oolong who has been terrorizing their town and kidnapping the villagers daughters.
After convincing him and the rest of the town, that they were not demons, Bulma asked the townspeople if they have seen a Dragon Ball nearby. An old woman of the village said that she has one, and agrees to give it to them as long as Bulma and Goku can get rid of Oolong and rescue the girls for them. Since no one in the village knows where Oolong's lair is, Bulma comes up with a plan to dress Goku up as Sherman Priest's daughter whom is Oolong's next target.
Oolong shows up later that day as a large, grotesque groom. The demon mistakes Goku's desire to pee for shyness and changes into a gentlemanly form. Seeing his new, handsome shape, Bulma runs out and attempts to woo Oolong. While thinking about which woman to choose, Oolong notices Goku peeing on a tree off to one side while still standing. Enraged at being tricked, Oolong changes into a gigantic bull. Goku gets rid of the girl's clothing and challenges Oolong to battle.
- Bulma pulls out the 4-star Dragon Ball out of her backpack when Goku is carrying it inside a sack tied to his sash.
- Sherman Priest's door says Sherman the Shaman on it in the English releases.
- During Oolong's daydream of his face between a woman's breasts the Breast were supposed to have nipples but they were removed in all the English releases.
- This entire chapter takes place on September 5, Age 749.
- This chapter begins the running gag of Goku patting peoples crotches to identify their gender.
- It is revealed that Bulma's bra size is 34-C.
- Oolong reveals that he is younger than Bulma who is 16.
- This is the first chapter to be censored.
- Only the first three pages of this chapter are available in color.