The Irish (2-1) dominated the boards against the Leopards (1-2), raced ahead by 16 points at halftime and steadily built their lead to 36 points late in the final period.
Luke Harangody, Notre Dame's burly freshman super-sub, added 18 points for his third straight game in double figures. Rob Kurz had 16 points, Tory Jackson added 10 points and Kyle McAlarney had 12 assists for the Irish.
Notre Dame led 46-30 at halftime, then Harangody had two baskets and two free throws in less than 3 minutes as the Irish built a 60-38 lead early in the second half. Notre Dame continued pulling away, and Harangody's final basket and one of two free throws by freshman Jonathon Peoples gave the Irish their biggest lead at 90-54 with less than 2 minutes remaining.
Lafayette, which did not get an offensive rebound or a point off turnovers until the closing minutes against Notre Dame's reserves, was led by the 10 points of Matt Betley, its only player in double figures.