Geoffrey Kiprono Mutai (born 7 October 1981) is a Kenyan long distance runner who specialises in road running competitions.

He also won the 2011 New York City Marathon with a time of 2 hours 5 minutes and 6 seconds (4:46 per mile pace), breaking the course record set by Tesfaye Jifar of Ethiopia in 2001,[3][4] and repeated his performance at the 2013 New York City Marathon with a time of 2 hours 8 minutes and 24 seconds.

At this race he met his current manager Gerard Van de Veen of Volare Sports, who provided him with the opportunity of competing abroad.

[8] He made significant improvements at the Eindhoven Marathon, setting a new personal best of 2:07:50, which was a course record and over a minute and a half ahead of the opposition.

[12] He returned to the Loopfestijn Voorthuizen race a few months later and improved upon his previous course record, running under 28 minutes for the first time to set a new best of 27:39.

[15] He won the Valencia Half Marathon in late 2009, seeing off the challenge from pre-race favourite Boniface Kirui and setting a new best of 59:30 over the distance.

[16] The Ras Al Khaimah Half Marathon was Mutai's first major race of 2010, and he beat Tadese Tola to the finish line.

[21] He was pitted against his Rotterdam rival Makau at the Berlin Marathon and the two maintained the same positions, with Mutai clocking 2:05:10 for second place.

[24] At the 2011 IAAF World Cross Country Championships he was among the lead pack with 500 m to go but was outstripped by the fast pace and finished fifth.

[27] In August he ran the Bogotá Half Marathon in a course record time of 1:02:20 hours, beating Deriba Merga by a margin of over two minutes.

[32] A world record attempt at the 2012 Berlin Marathon saw him run the fourth fastest time ever (2:04:15), winning just ahead of his training partner Dennis Kimetto.