Tricia Mallory, Emily Edenstrom, Cat Abitua and Jessica Toms each scored a goal as the Bearkats upped their 2011 season record to 2-3.
Mallory opened the scoring in the 9th minute on a pass from Edenstrom. The goal was the sophomore midfielder's second of the season.
Edenstrom scored in the 36th minute on an assist by Mallory to give Sam Houston a 2-0 halftime lead.
Grambling cut the margin to 2-1 with a goal in the 70th minute but the Kats bounced right back for a pair of quick goals.
Abitua fired in an unassisted goal in the 73rd minute and Toms tallied on a pass from Amanda Biega in the 74th minute.
Sam Houston travels to Houston to take on the Rice Owls Sunday at 7 p.m.