The 32-year-old has put pen to paper on a two-year deal and can now look forward to a new chapter in his career at the Matchroom Stadium.
McAnuff joins Orient after bringing the curtain down on a successful five-year spell with the Royals and he believes he has picked the right club to continue enjoying his football.
"It's been a long summer for me," McAnuff told Orient's official website. "I've had a few offers but have been waiting for the right fit and I believe I've found it here at Orient.
"The more I spoke to the manager and learned about the club, it just seems a great place to be."
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