The game was tied 16-16 at the first buzzer and the Eagles led 34-27 at halftime.
But the second half belonged to the Eagles, who outscored the Tigers 40-14 in the second and third quarters.
Four players scored in double figures for Kent City. Kaitlyn Geers led the way with 23 points, Zara Webber and Teanna McCuaig each scored 15 and Paige Mortensen added 11.
Jakayla Anderson led Muskegon Heights with 18 points and Danasia Day added 16.
The Eagles (17-4) advance to Friday’s district championship game against host Western Michigan Christian at 7 p.m.