Quinn is best known for his roles on four television series: as Sweeney the bartender on The Rifleman (co-starring Paul Fix); as Dr. Melnitz on The Odd Couple (with Garry Walberg); and as Mr. Van Rensselaer on All in the Family and its spin-off series, Archie Bunker's Place (both co-starring Jason Wingreen). He was also briefly attached to the TV series McMillan and Wife, starring John Schuck. He also appeared in several episodes of Mary Tyler Moore, The Bob Newhart Show, and The Rockford Files, among many others. He was the father-in-law of Bob Newhart.