"If She Knew" is a song by British R&B singer Lemar, released as the first single from his fourth album, The Reason.

The song has been a further top 20 success for Lemar; it was C-listed on BBC Radio 1, entering the UK Singles Chart at #61 after just two full days of download sales, and then climbing to #14 upon the release of the physical CD.

The following week the single fell to #19 but Radio 1 moved the track up to their B-list.

In a review from Digital Spy Alex Fletcher gave the song 3/5 and wrote, "For some reason he keeps his best vocals in the locker on 'If She Knew' and replaces his usual laid-back R&B with a futuristic pop sound that wouldn't sound out of place on a Kanye record.

The results are slick and satisfactory, but this sounds more like passable album fodder than a storming comeback track.