Bakary Sako is the latest free agent to join the club this season, with the Baggies confirming his arrival.
The former Wolves and Crystal Palace forward joins the club on a one-year contract after a successful trial period.
Sako left Selhurst Park in the summer after he was unable to shake off the injury problems that saw him miss large spells of the previous campaign.
Palace were reportedly keen to re-sign the player, but registration rules preventing them from doing so.
A host of Championship clubs, including Aston Villa and Nottingham Forest, were linked with a move for Sako, who boasts tremendous experience at this level.
His arrival gives Darren Moore another option in the final third, with competition for places heating up.
Sako will have a job in dislodging either Jay Rodriguez or Dwight Gayle after the two have formed one of the most potent partnerships in the division.