The 1981 Lacoste Cup, also known as the Cologne Cup, was a men's tennis tournament played on indoor carpet courts at the Sporthalle in Cologne, West Germany that was part of the 1981 Volvo Grand Prix circuit.

It was the sixth edition of the tournament and was held from 26 October through 1 November 1981.

First-seeded Ivan Lendl won the singles title.

[3] Ivan Lendl defeated Sandy Mayer 6–3, 6–3 Sandy Mayer / Frew McMillan defeated Jan Kodeš / Karl Meiler 6–0, 6–4