As runners-up in the 1968 Norwegian Cup, Mjøndalen men's football team represented Norway in the European Cup Winners' Cup in the following 1969–70 season. They were eliminated in the first round by Cardiff City who defeated Mjøndalen 12–2 on aggregate. After being promoted to the top division in 1971, Mjøndalen regularly played on the top-tier of Norwegian football in the 1970s and 1980s, and finished second in 1976 and 1986. Finishing runners-up in the league qualified them to represent Norway in the UEFA Cup the following season.