The 32-year old Sweden international has officially joined the Galaxy and will officially be added to the Galaxy roster pending the receipt of his P-1 visa and International Transfer Certificate (ITC).
Wilhelmsson has been training with the Galaxy recently and has done enough to win a deal which he is excited about.
"I'm very pleased to be here now the deal is done and I'm very excited to join the team," he said.
"I know the league has been progressing in the last few years and I'm very excited to play MLS. I'm looking forward to getting started, to getting on the field and it's a new adventure that starts now."