The 1990–91 season of the Balkans Cup club tournament was the 27th season of the competition. It was won by Romanian side Inter Sibiu in the final against Yugoslav Budućnost Titograd for their first title in the competition.
Quarter-finals
First leg
Second leg
Budućnost won 2–1 on aggregate.
OFI won 2–1 on aggregate.
Semi-finals
First leg
Second leg
Galatasaray 1–1 Budućnost on aggregate. Budućnost won on away goals.
Inter Sibiu 2–2 OFI Crete on aggregate. Inter Sibiu won on away goals.
Finals
First leg
Second leg
References
