Peter Mungai Warui (born 22 April 1981) is a Kenyan boxer. He competed in the men's light flyweight event at the 2016 Summer Olympics where he was eliminated in the quarterfinals.
Warui began boxing at the age of nine. As he could not afford gloves, he initially boxed bare-knuckled.
As an adult, Warui boxed for the Kenyan Police team while working as a police constable.
Warui finished in fourth place in the African qualifiers for the 2016 Summer Olympics. He qualified for the tournament finals after a Cameroonian boxer was disqualified.
In the round of 16, Warui defeated China's Lü Bin on a split decision. He attracted media attention for his flamboyant celebration after the win. In the quarter-finals, Warui was defeated by Cuban boxer Joahnys Argilagos.