Tony Hadley has taken a 25% shareholding in Bury St Edmunds-based Red Rat along with his manager John Glover.
The brewery has already produced a beer called Hadley's, proceeds from which are going to Action Medical Research, a favoured charity of the singer.
The beer was originally sold through Hadley's official website, but brewery founder Kevin McHenry is now seeking wider distribution.
McHenry said: "I went to see him in concert and he was drinking a well-known lager on stage, so about two weeks later I sent a late-night email to his manager offering to make a beer. "
Hadley added: "There's a lot of kudos that some famous people are getting out of having their own vineyard but real ale is a bit more earthy and gritty, which appeals to me."