Teuchi is the owner of the Ichiraku Ramen Bar. His daughter is Ayame, and she works at his Ramen bar. Right before the third stage of the Chūnin Exam, he treated Naruto to an expensive bowl of ramen, which surprised him. Some months later, Ayame was kidnapped by Hakaku, who wanted Teuchi's recipe. The recipe was just to remove the bitter taste from the soup.

(Source: Naruto Wiki)