"I Knew I Loved You" is a song by Australian pop duo Savage Garden, released through Roadshow Music and Columbia Records as the second single from their second and final studio album, Affirmation (1999). The song was created as an attempt to replicate the composition of Savage Garden's previous single "Truly Madly Deeply". The track was serviced to US adult contemporary and top 40 radio in September 1999 and was issued commercially in Australia on 28 September 1999.

Savage Garden were an Australian pop duo consisting of Darren Hayes on vocals and Daniel Jones on guitar, keyboards, and vocals; they formed in Brisbane, Queensland, in 1993. They were signed to John Woodruff's talent agency and achieved international success with their No. 1 hit singles "I Want You", "To the Moon and Back", "Truly Madly Deeply" (1997), and "I Knew I Loved You" (1999).