|2002 Radès||10,000 m|
|2001 Brisbane||10,000 m|
He began his career as a track specialist in the 5000 metres and 10,000 metres. He ran in the 10,000 m final at the 1999 World Championships in Athletics and finished in seventh place. He achieved his 5000 m best of 13:02.28 minutes at the Athletissima meeting in 2000 and ran his 10,000 m best of 27:07.55 minutes in Palo Alto, California the following year. In the longer event, he won a silver medal behind Assefa Mezgebu at the 2001 Goodwill Games and was the bronze medallist at the 2002 African Championships in Athletics.
He switched to road running in 2004: he won the Bay to Breakers 12 km race, and made his debut in the marathon in Chicago, finishing ninth overall. He was the runner-up twice in 2005, coming second at the Los Angeles Marathon and then at the Chicago Marathon. In the latter race he ran his personal best time of 2:07:09 hours, which was the third fastest time that year behind Chicago winner Felix Limo and Haile Gebrselassie. Maiyo was runner-up for a third consecutive time at the 2006 Boston Marathon, finishing in 2:08:21. He ran in Boston and Chicago in 2007, reaching the top six at both, and was among the top eight runners at the Amsterdam Marathon and Frankfurt Marathon in 2008.
- Maiyo Benjamin. Retrieved on 2011-02-06.
- Goodwill Games. GBR Athletics. Retrieved on 2011-02-06.
- African Championships. GBR Athletics. Retrieved on 2011-02-06.
- Bay to Breakers 12 km. Association of Road Racing Statisticians (2010-05-18). Retrieved on 2011-02-06.
- Marathon 2005. IAAF (2010-01-12). Retrieved on 2011-02-06.
- Maiyo Benjamin. Marathon Info. Retrieved on 2011-02-06.
- Ben Maiyo Archived July 21, 2011, at the Wayback Machine. KIMbia Athletics. Retrieved on 2011-02-06.