Laurie Ellis fouled Scott Boyd in the area and former Rovers midfielder Brittain converted for the hosts.
Mark Ferry's header almost levelled matters on 83 minutes but Ross County held on to claim their first victory in three matches.
Ross County: McGovern, Miller, Watt, Boyd, Morrison, Kettlewell (Scott 88), Vigurs, Lawson, Brittain, Barrowman (Wood 83), Craig (Gardyne 61). Subs Not Used: Malin, Keddie.
Booked: Vigurs.
Goals: Brittain 76 pen.
Raith: McGurn, Wilson, Gathuessi, Hill (Ferry 68), Ellis, Williamson, Murray, Walker, Darren Smith, Shields (Sloan 64), Weir (Amaya 78). Subs Not Used: O'Connor, Wedderburn.
Booked: Murray, Darren Smith, Amaya.
Att: 2,033
Ref: S Conroy
Source: BBC Sport
Source: BBC Sport