Smith made 7 of 13 from the floor and 15 of 18 from the line for the Matadors (6-10, 1-1 Big West).
Cal State Fullerton (8-7, 1-1) scored the first 10 points of the game, as the Matadors didn't make a basket until after five minutes. But CS Northridge went on a 15-point run - punctuated by Kendall Smith's dunk with 5:58 left in the first half- and led 31-24 at intermission.
CS Northridge scored the first eight points of the second half, and the lead hit 20 on Aaron Parks' jumper with 6:33 left. Cal State-Fullerton went on a 20-4 run to trim the deficit to five with 1:24 left, but CSN made 10 of 12 at the line down the stretch to hold on.
The Titans were led by a career-high 41 from Tre Coggins. Khalil Ahmad added 17 points.