"U Know What's Up" is a song by American R&B singer Donell Jones. It was written by Edward "Eddie F." Ferrell, Darren Lighty, Clifton Lighty, Balewa Muhammad, Anthony Hamilton, and Veronica McKenzie for his second studio album, Where I Wanna Be (1999), while production was helmed by Ferrell and Darren Lighty for Untouchables Entertainment.

Donell Jones is an American R&B singer, songwriter, and record producer from Chicago, Illinois. He met record producer Eddie F in the mid-1990s and signed with his record label Untouchables Entertainment, beginning his career as a songwriter for its parent label, LaFace Records. Through the labels, he released his debut studio album, My Heart (1996) to poor commercial reception, although it spawned his first Billboard Hot 100 entries with the singles "In the Hood" and his cover of Stevie Wonder's "Knocks Me Off My Feet."