The 25-year-old was out of action for the majority of last season after undergoing an operation in a bid to solve the problem, but it appears that the midfielder faces an additional two months on the sidelines after confirming that he will go under the knife again.
O'Hara tweeted: "Sorry to disappoint the fans but am having surgery tomorrow on my hernia – the first operation didn't seem to work so I'm now going to undergo a different type of hernia op.
"It's been a really frustrating time for me and I'm dying to get back on the pitch. I'm hoping to be fit in around eight weeks so I'll have a lot of the season left.
"I'd rather take my time now than rush it and have problems for the rest of my career. I'm still only 25 and got a long time in the game. Hopefully this will make me stronger, thanks for all the support."
O'Hara has been at Molineux on a permanent basis since last year.