Deshaun Thomas sparked a big second half, scoring 12 of his 14 points, and Evan Ravenel added 10 with five rebounds for the Buckeyes (20-7, 10-5 Big Ten).
Ohio State notched an eighth straight 20-win season under Coach Thad Matta.
Adreian Payne scored 12 points and grabbed 15 rebounds for the Spartans (22-6, 11-4), who dropped a second consecutive game.
The loss put them two games behind Big Ten leader Indiana with three contests remaining.
Gary Harris also reached double figures with 14 points for MSU.
Celebrity Couples of 2014 [PHOTOS]