The game was scheduled to be held in Calhoun Saturday, but was relocated to Rockmart due to wet field conditions.
The Rockmart team earned its spot in the championship game by defeating Calhoun in the semifinals.
The Heat advanced to the title game by beating Paulding County and Calhoun in the consolation bracket of the double-elimination event.
In the championship game on Saturday night — which had a delayed start of about 30 minutes due to lightning — Rome jumped out to a 2-1 lead in the second inning.
But Rockmart scored three runs in the fifth inning for a 5-2 lead, and added two more runs in the sixth en route to the win.
In addition to Rockmart and Rome, other teams competing in the tournament were from Trion, Murray County, Calhoun, Paulding County and Dalton.
Rockmart is also hosting the boys’ 9-and-10 state baseball championship, which began Saturday morning.
The tourney is scheduled to end next Friday.