“Knock You Down” is a song by American singer-songwriter Keri Hilson, taken from her debut studio album, In a Perfect World… (2009). The song features guest vocals from American singer-songwriter Ne-Yo and American rapper Kanye West. All three artists co-wrote the song with its producer Nate “Danja” Hills, as well as Kevin Cossom and Marcella “Ms. Lago” Araica. The song was released first released to rhythmic and urban airplay in the United States as the album’s fourth single in the US, and it would later serve as the third worldwide single.
The song is a hip-hop and R&B number, which includes elements of pop music. The lyrics of the song pertain to how love “knocks you down.” Part of the song refers to Michael Jackson; coincidentally it was released at the time surrounding the death of the singer.