Lani Young led Middlebury with 20 points, seven rebounds and five steals, and Emily Johnson chipped in 17 points, seven rebounds and five assists.
Plattsburgh shot 47.4 percent from the field in the first half, but trailed 36-22 at the break because Middlebury made five more field goals. For the game, the Cardinals were 17 of 45 for a 37.8 clip and the Panthers made 40.7 percent of their field goals.
Jessica Dooley contributed 10 points for the Cardinals.
Middlebury also won the battle on the glass with a 43-22 rebounding advantage.