Music critics have given the track generally favorable reviews.
Billboard described the song as a "melodic youth-oriented rocker" that uses "catchy handclaps" to generate the feel of an early 1960s song.
Cash Box said that "the guitar work is derivative but the enthusiasm is refreshing" and praised the vocals and organ playing.
AllMusic's Donald A. Guarisco called the song "one of the classics of the Cars' catalog",
Classic Rock History critic Brian Kachejian rated it as the Cars' 6th greatest song, praising
Elliot Easton's opening guitar
riff and saying that "The song has such a happy, good-time feel; you would think it’s a song about being happy in love when it’s really all about seeing one’s ex-girlfriend with the guy’s best friend." "My Best Friend's Girl" was ranked the 12th best song of 1978 by critics
Dave Marsh and Kevin Stein, and it was named one of "The 1001 Best Songs Ever" in a 2003 issue of
Q magazine. Some critics have noted the similarity in style of
Fountains of Wayne's 2003
hit single "
Stacy's Mom" to this song. ==Track listing==