The 31-year-old leaves the club having failed to score in 33 appearances.
The Sweden international signed for West Brom on a free transfer in August 2012.
"Markus Rosenberg has had his Albion contract cancelled by mutual consent and is now a free agent," the club stated on their official website.
Rosenberg wrote on Twitter: "Thanks to all staff and players at West Brom. And also a big thanks to all Baggies supporters."