West Brom are second from bottom in the Premier League after picking up only seven points from 13 games, their sole victory coming against Sheffield United late last month. They have also drawn four games and lost eight.
A statement from the club read: “West Bromwich Albion have today parted company with Head Coach Slaven Bilic.
“Assistant Coaches, Dean Racunica and Danilo Butorovic, and First Team Coach Julian Dicks have also left the club with immediate effect.
“Albion would like to thank Slaven and his coaching staff for their efforts in achieving promotion last season and wishes them all well in the future.
“The club will make no further comment at this time.”
Bilic, who was appointed West Brom boss in June 2019 and won promotion back to the Premier League last season, is the first top flight manager to lose his job this campaign.
Speaking after Tuesday’s credible draw at Manchester City, the 52-year-old did not appear to be a man under pressure.
“To be fair, I’m not bothered,” Bilic told reporters. “I’m doing my job. I’m enjoying it. I’m working hard for myself, for my staff, for the players, for the club, that’s all.
“Everything else is out of my control. I’m not really that bothered what’s happening behind the scenes. I don’t care.”
West Brom next host Aston Villa on Sunday.