Wood, a former alcoholic, started drinking again after he met Ekaterina Ivanova in a bar and has been consuming two bottles of vodka a day.
"Following Ronnie's continued battle with alcohol he has entered a period of rehab," The Sun quoted a spokesman for the star, as saying.
Ivanova, regularly visited the 61-year-old rocker in The Priory last month, and even stayed with him the last time he sought help.
According to sources, the part-time model and waitress stayed twice at the centre in Roehampton, South West London - without any knowledge to Wood's wife and family.
The liaison with the Russian waitress started when Ronnie had checked in after a wine-tasting session in the run up to his daughter Leah's wedding.
"Everyone thought this girl must have been Ronnie's daughter, but it quickly became apparent she wasn't. We then assumed she was a groupie," said a source.
And it was on July 16 that Ronnie finally left Ireland, where he had been with Ekaterina, after eventually answering calls from family and pals to get help.
It was also revealed that Ronnie did not participate in rehab meetings at the centre, even after checking in to beat the bottle.