Martin Irungu Mathathi (born 25 December 1985 in Nyahururu) is a Kenyan long-distance runner, who competes in track, cross country and road running events.

Mathathi was the 2010 winner of the men's short race at the Chiba Cross Country in Japan.

[1] He won the Sendai Half Marathon in a personal best time of 59:48 minutes, easily beating second placed Mekubo Mogusu.

[2] He gained selection for the 2011 World Championships in Athletics and came fifth for Kenya in the men's 10,000 m. That year, Mathathi set a course record for the Great North Run half marathon, finishing in a time of 58 minutes 56 seconds.

[8] He attempted to extend his undefeated streak at the Gifu Half Marathon and although he finished in 1:00:54 hours he was runner-up to world champion Zersenay Tadese.