The 26-year-old forward last month publicly expressed his desire to leave the club, having fallen down the pecking order at Old Trafford under Ralf Rangnick.
The dispute between player and manager then saw Martial forced to deny Rangnick's claims that he had refused to play against Aston Villa earlier this month, further fuelling speculation over his future.
Martial was involved in last weekend's late win over West Ham United, but he will now spend the rest of the 2021-22 campaign on loan with La Liga title hopefuls Sevilla.
"Manchester United forward Anthony Martial has joined Sevilla FC on loan for the remainder of the 2021-22 season," read a statement on Man United's official website.
"The Frenchman completed a medical in Andalusia, after the two clubs agreed terms for his temporary transfer. Everyone at the club wishes Anthony the best of luck for his time at Sevilla."
Martial could make his debut for Sevilla, who currently sit second in La Liga, when they face Osasuna on February 5. body check tags ::