Ross Jenkins threw for 97 yards and a touchdown as the Bulldogs (5-4, 3-2 WAC) recorded their first shutout in over 12 years.
Duke Ihenacho recorded 11 tackles and Carl Ihenacho had eight as the Spartans (6-4, 4-2 WAC) lost their second straight home game.
The Bulldogs intercepted two passes, leading to a pair of touchdowns, within 1:30 of the second quarter to open a 14-0 lead.
San Jose State quarterback Myles Eden, starting in place of Kyle Reed, was 3-of-8 with the two picks, for 11 yards before Reed, who was nursing a back injury, replaced him. Reed finished 4-of-14 for 79 yards, 62 coming on one play.
The Bulldogs' Weldon Brown intercepted a pass at the Spartans' 21-yard line. On the next play, Jackson ran for the 21-yard touchdown. Less than two minutes later, Terry Carter returned an interception 50 yards for a score.
San Jose State never really threatened in the contest, recording a season-low six first downs and 148 yards of total offense. The Spartans' best chance was a first-and-goal situation early in the fourth quarter. The Spartans lost yardage and threw incomplete on a fourth down play.
Dustin Mitchell caught a 35-yard pass from Jenkins in the fourth quarter to complete the scoring for the Bulldogs, who have won three of their last four games.
Louisiana Tech had scored a total of 24 points in its four previous road games. It could have been worse as the Bulldogs had a kickoff return for a touchdown called back because of a penalty and a punt return for a touchdown called back, also because of a penalty.