2004–05 OHL season

The 2004–05 OHL season was the 25th season of the Ontario Hockey League. Twenty teams each played 68 games. The J. Ross Robertson Cup was won by the London Knights, defeating the Ottawa 67's. The Knights also went on to win the Memorial Cup.

OHL Playoffs
London and Ottawa both advanced to the Memorial Cup tournament.

J. Ross Robertson Cup Finals
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ADT Canada-Russia Challenge
On November 25, the OHL All-stars defeated the Russian Selects 3–1 at Barrie, Ontario.

On November 28, the OHL All-stars defeated the Russian Selects 5–2 at Mississauga, Ontario.

The OHL has an all-time record of 4–0 against the Russian Selects since the tournament began in 2003–04.

London's 2004–05 Undefeated Streak
In the 2004–2005 season the London Knights broke an OHL record, going 28 games in a row without a loss (27–0–1). They subsequently broke the CHL record of 29 games (held by the 1978–79 Brandon Wheat Kings, who went 25–0–4 during their streak), with a 0–0 tie with the Guelph Storm on December 10, 2004, giving them a record of 28–0–2. The streak ended at 31 games after a 5–2 loss to the Sudbury Wolves on December 17.

* Tied OHL record previously set by Kitchener in 1983–84 ** Broke OHL record previously set by Kitchener in 1983–84 *** Tied CHL record previously set by Brandon in 1978–79 **** Broke CHL record previously set by Brandon in 1978–79