Rufus Rastus Johnson Brown was a song by Harry Von Tilzer, also known by its main title What You Goin' To Do When the Rent Come 'Round? ^[undefined] It was sold as sheet music. Later it was recorded in 1903.

The title character of the song also gave rise to a musical with song written by Ernest Hogan titles Rufus Rastus. Hogan reprised the character again in 1907 for a different musical.

Versions of the song's lyrics have included epthiets coon and nigger. The song was performed during an era of minstrel shows when performers would dress up in blackface and give caricatured renditions of song, dance, and comedy routines.

In 1969 Rufus Thomas recorded a funky version of the song with revised lyrics on his hit album Do the Funky Chicken.