If You Love Me, Let Me Know is a United States and Canada-only album by singer Olivia Newton-John, released in May 1974. Other than the title track, all the material was from her previous albums, Long Live Love (1974), Olivia (1972) and Music Makes My Day (1973). It is the first of her albums to top the Billboard 200 pop albums chart. Two hit singles were issued from the LP in the U.S.: the title song and "I Honestly Love You", the latter of which became Newton-John's first number-one U.S. single.

"If You Love Me (Let Me Know)" is a song written by John Rostill that was a 1974 hit single for Olivia Newton-John. It was her second release to hit the top 10 in the United States, reaching number 5 on the pop charts and number 2 on the Easy Listening chart. It also reached 2 on the Billboard country chart. As with her single "Let Me Be There", Mike Sammes sings a bass harmony.