As an amateur, he frequently played for the United States men's national ice hockey team.

Lilyholm was a member of Team USA at the 1968 Winter Olympics and the 1966, 1967, 1970, 1971, and 1974 Ice Hockey World Championships.

Outside hockey, Len Lilyholm was an architect and builder who participated in the design of the St. Paul Civic Center, the Saints' new home arena which was completed in January 1973.

[2][3] Lilyholm died at the age of 83 in a head-on traffic collision along with his wife, Carol, on Interstate 35 in Worth County, Iowa on December 28, 2024.

Lilyholm, the driver, crossed over the median and drove southbound in the northbound lanes before hitting another car head-on.