The Crimson took a commanding 7-1 first half lead on a quick shot off a kick-out move by junior utility Rob Collier.
Harvard did not relent in the second half as Crosby and Bazylewicz each had easy goals and the Crimson sent DarTmouth packing in the fourth quarter with two more strikes.
All told, the weekend sweep extended Harvard's win streak to ten games.
"We're pretty happy with the way the season is going and keeping the win streak alive is a good thing," said Bleisath. "
The Crimson will face the four league opponents next weekend at Amherst, in its quest for a bid in the ECAC and Northern Regional tournaments.
"Going into next weekend, these games are good preparation," said Collier. "We're going to have to play big and want it more than our opponents. It's a matter of staying focused and keeping up our enthusiasm."