The veteran winger, 36, has been picked by manager Justin Edinburgh to lead the team out.
McAnuff will complete 100 appearances for the club in August and already a fans’ favourite, he will take the Orient armband full time.
Midfielder Charlie Lee has been appointed vice captain for the new campaign.
McAnuff told the club’s website: “To be made captain of this club is a massive honour.
“It's something I've been fortunate enough to do previously in my career and initially got given it when Ross Embleton took over last year, it's something I've really enjoyed.
“I'm very proud to have been asked and it's something I enjoy and will hopefully do a good job of it."
Edinburgh said: "Not only does he lead by example on the pitch, he's unbelievable off it.
“He does it with class and integrity and what that does allow is Charlie to continue his comeback from a long-term injury without any distractions.”