In the running: Athlete of the Year award contenders announced
The athletics governing body said Monday that the trio gathered the most votes in a three-week poll.
The award will know its winner at a ceremony as part of the IAAF's centenary celebrations in Barcelona on November 24.
Bolt became the first man to win back-to-back Olympic titles in both 100- and 200-meter events. The Jamaican also holds the world record in both distances.
Merritt won the 110 hurdles in London. The American went on to set a world record of 12.80 seconds at the Van Damme Memorial in Brussels a month after the Olympics.
Kenyan star Rudisha won the 800 at the games with a world record of 1 minute, 40.91 seconds beating the previous best mark set by another ethnic Kenyan Wilson Kipketer in 1997.
Kenya's David Lekuta Rudisha (L) and Aries Merritt of the US (AFP Photo/Eric Feferberg/Adrian Dennis)