TRIVIAL PURSUITS: What is the Longest-Running American TV Series?

September 14, 2010 ( – On September 13, 1990, “two separate, yet equally important groups” made their NBC network debut as “Law and Order” premiered. 


That series finally completed its run – and 20th season on May 24, 2010, placing it in a tie for the longest-running live action series on American TV.  With what series does it now share that record? 


Answer:  “Gunsmoke.”   


A radio version ran from 1952 to 1961 (William Conrad, who went on to fame in the “Cannon” tv series in the 1970s, played Marshall Matt Dillon), but the television version ran for 20 seasons; from 1955 to 1975.   

Now, as it turns out it “Gunsmoke” is still the United States’ longest-running prime time, live-action drama with 635 episodes.  “Law and Order” also ran for 20 seasons, but only booked 476 episodes.