1946 was the first season for Ainslie in First Grade since 1941 due to the War.
There were 6 teams in the First Grade Competition, Acton, Ainslie, Eastlake, Queanbeyan and RMC.
With 3 rounds to go in the home and away Ainslie were outside the top four. They defeated Queanbeyan, Acton and drew with Manuka in the last round to grab fourth position.
Ainslie played Manuka in the First Semi-Final at Northbourne Oval. They had a convincing win over Mauka winning by 56 points.
- Final score: Ainslie 20.15-135 def Manuka 12.7-79
- Best for Ainslie: Stevens, Thompson, Backen, Furler, Dee, Bloomfield, Davies.
Ainslie played Queanbeyan in the Preliminary Final for the right to play Eastlake in the Grand Final.
Ainslie had another convincing win this time defeating Queanbeyan by 88 points.
- Final score: Ainslie 18.22-130 def Queanbeyan 6.6-42
- Goal kickers for Ainslie: Mulligan 5, Thompson 5, McCulloch 4, Davies 2, Dee 1, Furler 1.
- Best: R Furler, S Dee, A Stevens, J Backen, Thompson, Mulligan, Connelly.
The Ainslie team for the Grand Final against Eastlake was:
- Stevens (Capt.)
- Connelly (V.Capt.)
- A Furler
- R Furler
Ainslie and Eastlake played off in the Grand Final at Manuka Oval on 28 September. Eastlake were coming off a run of 16 consecutive wins and had not been beaten by Ainslie during the season. Ainslie won the 1946 Premiership by defeating Eastlake by 37 points in the Grand Final.
- Final score: Ainslie 12.19-91 def Eastlake 8.6-54
- Best: John Wilkinson, Alan Stevens, Bob Bloomfield, Robert Furler, Gerry Bowen, Sam Dee, Jim Backen, Lorence Thompson
Alan ‘Ginty’ Stevens won the 1946 Mulrooney Medal. Stevens had returned to Ainslie in 1946 after playing with the Eastlake-Manuka combine side during the war years. He also saw active service in the war.