Linet Chepkwemoi Masai (born 5 December 1989) is a Kenyan professional long-distance runner who competes in track and cross country running events.

She started running in 2005, when her older brother Moses Ndiema Masai won 5000 and 10000 metres at the African Junior Championships, hoping she would emulate his success.

She won the women's junior race at the 2007 IAAF World Cross Country Championships held in Mombasa, Kenya.

[8] At the 2010 World Cross Country Championships, she started strongly and began to build up a lead in the final lap.

[10] In August she signed up for the Women's 5K Challenge in London and comfortably beat Sylvia Kibet to win the race, reversing their positions from the previous year's competition.

[11] She entered the 10,000 m at the 2010 African Championships in Athletics but Tirunesh Dibaba defended her title while the Kenyan left with a bronze medal.

[12] At the Memorial van Damme (the final for the 2010 IAAF Diamond League) she finished third as compatriot Vivian Cheruiyot took the inaugural event title.

[17] History repeated itself for a third time for Masai at the 2011 IAAF World Cross Country Championships as she led early on but was pushed into second place by a Kenyan rival yet again in the form of a quick-finishing Cheruiyot.

[19] On the 2011 IAAF Diamond League circuit she placed in the top three in Shanghai, Eugene, and the final in Zürich, but was someway behind Vivian Cheruiyot, who defended her 5000 m title.