"I'm in Love Again" is a 1956 single by Fats Domino. The song was written by Domino and his longtime collaborator, Dave Bartholomew. The single was Domino's third number one on the R&B Best Sellers list, where it stayed at the top for seven weeks. "I'm in Love Again" also peaked at number three for two weeks on the pop chart. "I'm in Love Again" was a double-sided hit for Domino as the B-side of the pop standard, "My Blue Heaven".

Bill Haley and His Comets covered this song on their 1960 covers album Bill Haley and His Comets.

The Animals covered it on both their US debut album The Animals, MGM Records – SE 4264, and their UK debut album also called The Animals, Columbia (EMI) 33SX 1669, in 1964.

Paul McCartney recorded the song during his CHOBA B CCCP album sessions. It was released as a b-side for "This One" single and on 1991 international edition of CHOBA B CCCP.

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