Humby, a native of Winnipeg who now makes his home in Los Angeles, is missing a right hand as a result of his arm being caught on his mother's umbilical cord and severed while in the womb.
He is the current International Muay Thai Council world super-welterweight champion.
He is up against MMA fighter Kyle Maynard, wheelchair racer Raymond Martin, cyclist Oz Sanchez and skier Tyler Walker.
Toronto's Dwayne de Rosario of D.C. United is a candidate for best MLS player, along with David Beckham (Los Angeles Galaxy), Brad Davis (Houston Dynamo) and Chris Wondolowski (San Jose Earthquakes).
Montreal freestyle skier Kaya Turski, a three-time Winter X Games champion in slopestyle, is nominated for best female action sports athlete.
The Stanley Cup-champion Los Angeles Kings are well showcased in the Espy nominees.
The Kings are up for best team and best upset, while goalie Jonathan Quick is nominated in the best championship performance and best NHL player categories. Darryl Sutter is up for best coach/manager.
Other best NHL player finalists are Claude Giroux of the Philadelphia Flyers, Henrik Lundqvist of the New York Rangers, Evgeni Malkin of the Pittsburgh Penguins and Steven Stamkos of the Tampa Bay Lightning.
Sidney Crosby is nominated for best comeback athlete.
Other best team nominees are Alabama football, Baylor women's basketball, Kentucky men's basketball, Miami Heat, New York Giants and St. Louis Cardinals.
Best male athlete is between tennis star Novak Djokovic, LeBron James of the Miami Heat, Green Bay Packers quarterback Aaron Rodgers and Detroit Tiger Justin Verlander.
Best female athlete nominees are Baylor basketball player Brittney Griner, tennis star Maria Sharapova, skier Lindsey Vonn and U.S soccer international Abby Wambach.
Best fighter is between MMA champions Jon (Bones) Jones and Anderson Silva and boxers Floyd Mayweather Jr. and Andre Ward.
Mexican Mario Gutierrez, who calls Vancouver his second home, is up for best jockey.
Winners of the Internet vote will be announced July 11 in Los Angeles.