The Singapore Cup 2009 (known as the RHB Singapore Cup due to its main sponsor) started on 27 April 2009. It was the 12th staging of the annual Singapore Cup tournament. 12 S.League clubs and 4 invited foreign teams from Thailand (2 teams), Cambodia (1) and Indonesia (1) played in this edition. The cup was a single-elimination tournament, with all sixteen teams playing from the first round. The first round involved one-off matches. Subsequent rounds involved ties of two legs. The final was played on 8 November and won by Geylang United, who beat Bangkok Glass 1–0. The cup winner were guaranteed a place in the 2010 AFC Cup.

Teams

Knockout stage

The draw for the tournament was held on 15 April 2009

Bracket

Preliminary round

Quarter-finals

First leg

Second leg

TTM Samut Sakhon won 7 – 3 on aggregate. Bangkok Glass won 5 – 4 on aggregate. Geylang United won 4 – 3 on aggregate. ''Albirex Niigata (S) 1 – 1 Tampines Rovers on aggregate. Albirex Niigata (S) won 3 – 1 on penalties.''

Semifinals

First leg

Second leg

''Geylang United 1 – 1 Albirex Niigata (S) on aggregate. Geylang United won 4-3 on penalties.'' Bangkok Glass won 9 – 4 on aggregate.

Third Place Playoff

Final