Peter Cheruiyot Kirui (born 2 January 1988) is a Kenyan long-distance runner who competes over 10,000 metres on the track and in road running competitions. He was the 2011 Kenyan champion over 10,000 m and came sixth at the 2011 World Championships in Athletics. He has acted as a pacemaker for major marathons (including Patrick Makau's world record in 2011) and has a marathon best of 2:06:31 hours. His best for the half marathon is 59:39 minutes.
Hailing from Bomet in Kenya, Kirui had his first foreign competition at the Cursa de Bombers in Barcelona and was runner-up to Josphat Menjo. He won the Carreira Popular in La Coruña in 2009 and was also fourth at the 15 km Villa de Massamagrell that year (which was also won by Menjo). He made his half marathon debut in 2009 and made the top four at the Nice Half Marathon, Udine Half Marathon and the Baringo Half Marathon. He ran on the track in Spain that summer, recording a 3000 metres best of 7:45.79 minutes in Zaragoza and a 5000 metres best of 13:15.90 minutes at the Barcelona Athletics Meeting.
At the start of 2010 he was runner-up at the Berlin Half Marathon, finishing just one second behind winner Eshetu Wondimu. He finished fifth at the Paderborn Easter Run. He ran in a series of races in the United States, winning the Lilac Bloomsday Run and taking the runner-up spots at the Utica Boilermaker, Peachtree Road Race and Bay to Breakers. He proved himself to be a competent pacemaker that year: he paced Patrick Makau to a time of 2:04:48 hours at the Rotterdam Marathon in April and helped Samuel Wanjiru to a time of 2:06:24 at the 2010 Chicago Marathon. Kirui closed his season with a ninth place finish at the New Delhi Half Marathon.