Stephen Lumpkins added 16 points to help the Eagles (11-5, 1-0) to their fourth-straight win in a meeting of the last three conference champions.
C.J. McCollum nearly matched Moldoveanu, scoring 23 of his 32 points after halftime as the Mountain Hawks (9-7, 0-1) suffered their first loss in four games, and their first defeat to American since Feb. 7, 2009.
Mackey McKnight and Holden Greiner added 11 points each for Lehigh, which won last season's league title, after American won it in 2008 and 2009.
American trailed by as many as six points early in the second half, but Moldoveanu scored 19 of his team's 21 points during a stretch when the Eagles transformed a 47-44 deficit into a 65-55 lead.