"Baby Blue" is a song recorded by the band Badfinger for inclusion on their 1971 album, Straight Up. The song was written by Pete Ham, produced by Todd Rundgren, and released on Apple Records. It regained fame four decades later upon being featured in the series finale of AMC's Breaking Bad, which uses the track's title lyric as a reference to the special and iconic blue methamphetamine produced by main character Walter White.

Ham wrote the song about a woman named Dixie Armstrong, whom he had dated during Badfinger's last US tour.

"Baby Blue" was released as a single in the US on 6 March 1972, in a blue-tinted picture sleeve and featuring a new mix. Because Al Steckler, the head of Apple US, felt that it needed a stronger hook in the opening, he remixed the track with engineer Eddie Kramer in February 1972, applying heavy reverb to the snare during the first verse and middle eight. It was the group's last Top 20 single, peaking at number 14 on the Billboard Pop Singles chart.

However, the chaos that was enveloping the Apple UK operation at the time was strongly evident with regard to this song. While Apple US gave the song a picture sleeve and a remix to ensure that it was a hit, Apple UK remained unaware of its commercial potential. Although the single was even assigned a release number for the UK (Apple 42), "Baby Blue" was never actually released as a UK single.

Despite Badfinger's four top-20 Apple singles, Badfinger would only release one more single on Apple Records, "Apple of My Eye" in December 1973.

Aimee Mann covered the song as the B-side to her 1993 single "I Should've Known".

Singer-songwriter Barbara Manning covered the song with her band, S.F. Seals, on the 1994 album "Nowhere" (Matador Records).

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