Miller, playing with four fouls, made a back-door cut and Caleb Donnelly found him for the game-winner. Miller finished with 13 points and eight rebounds.
Quincy Ford scored 18 points with 14 rebounds for the Huskies (10-5, 2-0 Colonial Athletic Association).
Northeastern led by five at intermission and by as many as 10 in the second half. But UNCW chipped away and tied it at 58 on a Flemmings jumper with 4:08 to go. Flemmings' layup with 30 seconds left forged another tie before Miller won it for Northeastern.