"Time After Time" is a 1983 song by American singer-songwriter Cyndi Lauper, co-written with Rob Hyman. It was the second single released from her debut studio album, She's So Unusual (1983), with Hyman contributing backing vocals. The track was produced by Rick Chertoff and released as a single on January 27, 1984. The song became Lauper's first number 1 hit in the U.S. The song was written in the album's final stages, after "Girls Just Wanna Have Fun", "She Bop" and "All Through the Night" had been written. The writing began with the title, which Lauper had seen in TV Guide magazine, referring to the science fiction film Time After Time (1979).

Music critics gave the song positive reviews, with many commending the song for being a solid and memorable love song. The song has been selected as one of the Best Love Songs of All Time by many media outlets, including Rolling Stone, Nerve, MTV and many others. "Time After Time" was also nominated for a Grammy Award for Song of the Year at the 1985 edition. The song was a success on the charts, becoming her first number-one single on the US Billboard Hot 100 chart on June 9, 1984, and remaining there for two weeks. The song reached number three on the UK Singles Chart and number six on the ARIA Singles Chart.