The general consensus is that this song is about Noel Gallagher's then-girlfriend Meg Mathews, who is compared with a schoolboy's wall to which posters of footballers and pop stars are attached. He told Select magazine at the time: "It's about my girlfriend. She was out of work, and that, a bit down on her luck, so it's just saying, 'Cheer up and f---in get on with it.'" Noel later married then divorced Meg Mathews. However, according to Q magazine's 1001 Best Songs Ever, this was not about Mathews. Noel is quoted as saying, "The meaning of that song was taken away from me by the media who jumped on it. And how do you tell your Mrs. it's not about her once she's read it is? It's about an imaginary friend who's going to come and save you from yourself."

The music is based on Wonderwall Music, an instrumental album George Harrison wrote for the movie Wonderwall in 1968. This was the first solo album released by any of The Beatles.

The concept of the "Wonderwall" is based on a '60s film called Wonderwall - from Psychedelia to Surrealism, starring Jane Birkin. She lives next door to a man who becomes fascinated with her,so he slowly makes holes in his wall so he can watch her through it. This is the "Wonderwall." Warning: this movie is supposedly terrible.