The actress, who plays Dot Branning in the soap, said that she thinks the December 11 performance at the Brighton Dome will be a great way to mark the festive season.
Brown told The Argus: "I'm really looking forward to joining the Brighton Gay Men's Chorus for their Christmas show. I can't think of a better way to kick-start the festive season while raising money for such worthy charities as the Chorus and the Sussex Beacon."
Comedian Zoe Lyons will compere the show, while cabaret singer Lorraine Bowen and vocalist Jodie Spencer will also make special appearances.
Lyons said: "I am totally delighted to be part of the Brighton Gay Men's Chorus show at the Dome, particularly as it is helping to raise funds for Sussex Beacon who provide such vital services for men and women living with HIV/AIDS.
"As well as continuing to provide excellent outpatient facilities there is an urgent need to raise money to keep the inpatient ward open. By coming to 'Pull a Cracker', the audience will not only be getting right into the Yuletime swing but also contributing towards another great cause this Christmas."
Brighton Gay Men's Chorus hope that the event will help challenge prejudices and raise awareness of issues within their community.
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