Jim Dolan’s pet music project is looking more like a full-time job.

After opening for the Eagles at his own venue in September, the Madison Square Garden boss has a new song on the soundtrack of Bill Murray’s upcoming comedy, “St. Vincent,” he told On the Money.

Dolan co-wrote the tune, “Hard to Find,” with Marc Copley. The two also partnered on “Violet’s Song” for last year’s Oscar-nominated Weinstein Co. movie, “August: Osage County.”

Dolan’s band, JD and the Straight Shot, also have a new album, “Where I’ve Been,” distributed by Caroline Music, due this month.

The 59-year-old billionaire, who owns the Knicks and the Rangers, is known for writing bluesy songs with lyrics that tackle social issues and poke fun at politicians.