Marco Banegas-Flores had nine points for the Huskies (3-1).
Josh Fox scored 14 points for the Highlanders (1-4).
Northeastern plays the winner of Wednesday's later game between Belmont and Alaska-Anchorage in the semifinals on Friday, while UC Riverside plays the loser in a consolation semi.
The Huskies took control early with a 12-0 run in a 4:29 stretch of the first half that gave them a double-digit lead they maintained for much of the rest of the way. UC Riverside got within 57-52 on Chris Harriel's 3-pointer with 1:04 remaining, but Northeastern protected the lead at the free-throw line.
This is Northeastern's second appearance in the Great Alaska Shootout. In 1986, the Reggie Lewis-led Huskies shocked No. 2-ranked and defending national champion Louisville en route to the championship game, where they lost to 10th-ranked Iowa.