Uthman belonged to the Umayyad section of the Quraish. He was the son of Affan, who was the son of Abi Al A'as, who was the son of Umayyah, who was the son of Abd Shams, who was the son Abd Manaf.

The Holy Prophet was the son of Abdullah, who was the son of Abdul Muttalib, who was the son of Hashim, who was the son of Abd Manaf.

Abd Manaf was the common ancestor of the Holy Prophet as well as Uthman. Abd Shams and Hashim were the two sons of Abd Manaf. The Holy Prophet was descended from Hashim, while Uthman was a descendant of Abd Shams. The Holy Prophet was fourth in descent from Abd Manaf, while Uthman was fifth in descent from Abd Manaf. Affan the father of Uthman was thus a second cousin of the Holy Prophet, and Uthman was a nephew of the Holy Prophet.

On the mother's side Uthman's relationship with the Holy Prophet was still closer. His mother was Urwa. She was the daughter of Kariz, who was the son of Rabeah,who was the son of Habib who was the son of Abd Shams.

Urwa's mother was Umm Hakim who was a sister of the Holy Prophet's father. Urwa was thus a first cousin of the Holy Prophet. On this basis, Uthman was a nephew of the Holy Prophet both on the side of the father as well as the mother.