"Days of the Week" is a song by Stone Temple Pilots, released as a single from their album Shangri-La Dee Da in 2001. The song also appears on the compilation albums Thank You and Buy This.

Despite being a moderate rock radio hit, the song did not endure STP's set list. The last time it was performed in any aspect was a partial performance of the song on November 13, 2001, and the last time the song was played in full was on November 3, 2001.^{[citation needed]}

The song's lyrics were written by vocalist Scott Weiland about how his heroin addiction affected his relationship with his second wife Mary Forsberg. The song's music was written by guitarist Dean DeLeo and has a much poppier sound than most of the band's previous singles.^{[citation needed]}

The music video depicts two STPs: one dressed up in white shirts and ties going door-to-door like salesmen or possibly missionaries, and the other taking a journey through space.^{[citation needed]}