For this season, former All-star winner Gerry McEntee transferred from Nobber to Summerhill. However, in the SFC final drawn game, he broke his wrist.
Navan O'Mahonys were the defending champions after they defeated Skryne in the previous years final, and they successfully defended their title to claim their 15th S.F.C. title (their 4th in a row) when beating Summerhill 1–11 to 0-5 after a replay in the final at
Pairc Tailteann on 28 October 1990. Colm Ratty raised the Keegan Cup for O'Mahonys while Mick Lyons of Summerhill claimed the 'Man of the Match' award, becoming the second man to claim this accolade after losing the final. Joe Cassells
also won a record 8th S.F.C. medal, although he was sent off in the replay.
The teams in the quarter-finals are the second placed teams from each group and the group C winner. The teams in the semi-finals are group A and B winners along with the quarter-final winners.
Gaeil Colmcille failed to fulfil their quarter-final fixture with Summerhill causing the game to be cancelled. At a County Board meeting on Wednesday 8 August, Gaeil Colmcille argued they didn't fulfil the fixture as four of their players were on holiday at the time and they felt they wouldn't do themselves or their spectators justice. The Kells side were then expelled from the championship.