The 1991 Tennents' Sixes was the eighth staging of the indoor 6-a-side football tournament. It was held at the Scottish Exhibition and Conference Centre (SECC) in Glasgow on 20 and 21 January.
Clubs from the 1990–91 Scottish Premier Division season competed, except Rangers who were replaced by First Division side Airdrieonains. The two group winners and runners-up qualified to the semi-finals; in the final Hearts beat Motherwell 5–2 to win their second Sixes title (a year after Edinburgh rivals Hibernian won the tournament).
Group 1
Group 2
Semi-finals
Final
Hearts beat Motherwell to win the tournament again. Joe Jordan was the respective winning manager of Hearts.
Prize money
A breakdown of the prize money from the tournament sponsors.
Other moments
SFA introduced a rule change. A team must keep a minimum of two players instead of one in opposition half. It was to encourage more goals being scored. Elgin City (Highland League Cup holders) played St Patrick's (East of Scotland Amateur Cup holders) in an exhibition match.