Utah State answered each of Boise State's first two scores, but the unbeaten Broncos then began pouring it on to improve their hopes of playing in a BCS bowl game.
Boise State (10-0) needs victories over Nevada and New Mexico State to finish off a perfect regular season.
Nevada will take a 6-0 Western Athletic Conference record into its game against New Mexico State Saturday and will meet Boise State next week with the league title on the line.
Martin gave the Broncos a 14-7 lead with a 17-yard touchdown run midway through the second period, then scored on a 2-yard blast to put Boise State in front for good with 4:47 left in the half. His 1-yarder with just 5 seconds to play in the second period gave the Broncos a 35-14 advantage.
Martin added a 6-yard scoring run in the fourth period and finished with 121 yards on 13 carries.
After Martin's second touchdown put Boise State in front 21-14, Utah State's Robert Turbin fumbled the ball away at his own 9-yard line. Jeremy Avery scored on the next play for the Broncos and the rout was on.
Boise State quarterback Kellen Moore completed 15-of-29 passes for 233 yards with one touchdown and no interceptions.
Utah State fell to 3-8 for the season and to 2-5 in conference play.