"I Think I Love You" is a song composed by songwriter Tony Romeo in 1970. It was released as the debut single by The Partridge Family pop group, featuring David Cassidy on lead vocals and Shirley Jones on background vocals. The Partridge Family version was a number-one hit on the Billboard Hot 100 in November 1970. The alternative rock band Voice of the Beehive scored a hit cover version of their own in 1991. There have also been many other cover versions of this song, most notably, Perry Como, Kaci, Katie Cassidy, Paul Westerberg, Constantine Maroulis, and the new In Search of the Partridge Family cast on VH1.

The single was produced by Wes Farrell and issued on Bell Records a month before the debut of the network television musical sitcom The Partridge Family. During the show's first season the song was featured on the show twice as it was climbing the actual Billboard charts. The single hit number one on the U.S. Billboard Hot 100 chart and in Canada on the RPM 100 national Top Singles chart in November of that year and number 1 in Australia in 1971.

The only cast members of the television show to actually sing on the recording of the song were David Cassidy and Shirley Jones. The music on the song was played by veteran studio musicians such as Hal Blaine, Larry Knechtel, Joe Osborne, Louie Shelton, Tommy Tedesco, and other L.A. session musicians from the Wrecking Crew. Background vocals on this, and all other Partridge Family recordings, were provided by veteran session singers: Ron Hicklin, John Bahler, Tom Bahler, and Jackie Ward.

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