Mike Barson was working driving a van and delivering bananas teamed with a co-worker who was always talking about “My girl did this” and “My girl did that”.[6][7] Barson used this phrasing to write a song about his own experiences with his girlfriend at the time, photographer Kerstin Rodgers.[8] Barson originally performed lead vocals on the song and sang on the original demo.
The song first made its way into the band's set when they were performing as The Invaders.[9] The first performance of the song came in July 1978, when the band performed at a shop in Camden Lock called Blind Alley where band member Mark Bedford was working; at the time the song was simply titled "New Song".[9]Suggs took over the vocal duties from Barson before long, and sang the album version of the song.[10]
When the group performed the song on Top of the Pops in January 1980, they were the first band of the new decade performing on the TV show.[11]
The music video for "My Girl" features Madness performing the song at the Dublin Castle, Camden.[10] For the video, the stage was extended especially, in order to ensure that the band could perform comfortably.[10]
Mike Nicholls of Record Mirror noted the contrast between "My Girl" and the band's previous single, "One Step Beyond". He felt "My Girl" to be a "Cockney/Dury-style lament" and "more indicative of the Kilburn and the High Roads side of Madness' sound".[12]
On 2 May 2008, Graham McPherson (Suggs) and Carl Smyth (Chas Smash) performed a new arrangement by Pet Shop Boys live at Heaven in London; they appeared as part of Pet Shop Boys' live set during Can You Bear It?, the benefit evening for Dainton Connell's family.[13] A Pet Shop Boys version of the song appears on the Pet Shop Boys' Christmas EP, along with a remix of the song.
Barson wrote a follow-up song, "My Girl 2", which was recorded by Madness and released as a single in 2012. Though it contains the phrase "my girl", "My Girl 2" is otherwise musically and lyrically quite distinct from "My Girl".
Audio Bullys included it on their 2003 instalment of the Back to Mine series of 'after hours grooving' DJ mix albums, with Tom Dinsdale referring to it as "Classic Madness", adding "everyone should be able to relate to this tune".[14]
Tracey Ullman covered Madness's "My Girl" in 1984.[17] The lyric and title were changed to "My Guy's Mad at Me". Madness' Mark Bedford played bass on the track. Her version was in the UK Top 40 at the same time as Madness' "Michael Caine" and peaked at number 23.[18] The music video featured the British politician Neil Kinnock, at the time the Leader of the Opposition.[19] The single was also released as a 7" picture disc, with a picture of Ullman and Kinnock sitting at a table.