Malik Gill added 14 points for the Big Green (11-14, 4-7 Ivy League), who shot 60.4 percent (29 for 48). They improved to 13-1 when holding teams below 40 percent shooting - Columbia was 35.5 percent (22 for 60). They are 2-9 when opponents hit at least 40 percent.
Kyle Castlin had 18 points and Maodo Lo 15 for the Lions (13-12, 5-6).
Dartmouth, which led 40-38 at the half, broke away from a tie at 51 midway through the second half with nine straight points, capped by Gill's 3-pointer at 7:32.
The Big Green got a John Golden 3-poitner, Gill three-point play and a Mitola 3 on consecutive possessions to lead 69-55 with 5:19 to play. They made 11 of 12 free throws in the final 2:18 before missing their last two.