Riddle, of Sherwood Park, Alta., finished with a second run of 90.60 points in snowy conditions at Rosa Khutor Extreme Park.
Calgary's Noah Bowman finished fifth in the final, while Justin Dorey of Vernon, B.C., missed jumps in both his final runs and ended up 12th.
David Wise of the United States won gold, while France's Kevin Rolland took bronze.
Matt Margetts of Penticton, B.C., fell in his second qualifying run and missed the cut for the 12-man final.
Ski halfpipe is making its Olympic debut in Sochi.