Campaigners are calling on Merton Council to save their pub from being developed into a supermarket or block of flats.
A petition launched on Tuesday, February 11 to save the Provenance in Colliers Wood High Street has been signed by 180 people.
The much-loved pub will close its doors on Sunday, February 23 for the last time.
Andrew Bowden, a product manager and pub regular who started the petition, said: "I was trying to get the community to have a bit of a voice and say in the pub's future.
"Pubs are not well-protected from the planning system so it's very easy for developers to shut them down and turn them into housing and supermarkets."
Protesters are urging the council to make the pub an 'asset of community value,' which would stall the sale of the building, allowing the community to prepare a bid to buy it.
Natalie O'Donnell, a part-time barmaid at the pub, said: "It has brought a real sense of community to the place and I just think it would be a shame if it was closed and never re-opened."
Antic pubs took over the pub last May but said owner, Punch Taverns, is selling the property after asbestos, broken glass, fencing and detergents were found in the garden.
"I spoke to Punch Taverns and Antic London and Antic is leaving on February 26 and there is a new purchaser. It's a very hard time for pubs."
Councillor Nick Draper, cabinet member for community and culture, said: "My sympathy is with the petitioners but I really can't see how it's going to succeed.
"The amount of money concerned is so high that local people aren't going to be able to afford it and the council doesn't have the money to buy it."
An event called 'last orders' will be held at the pub on Sunday, February 23 at a live music event to say farewell to patrons.