Marc Hoppler scored for the hosts off of a Jackson Goyette assist in the 14th minute minute to put the Maroons on top to stay.
Roanoke, on goals in the 40th and 45th minutes, took a 4-1 lead into the break.
The Maroons scored 44 seconds into the second half to provide the final margin of victory.
RC outshot Shenandoah 14-6 and were awarded eight of the game's 13 corners.
Shenandoah steps out-of-conference on Wednesday for a 7 p.m. home contest versus McDaniel.