Bingley and District Working Men's Club, in York Place, faces a bleak future after planning officers urged Bradford Council to refuse permission for about half of the building to become a mini market.
Club membership has already been decimated since the smoking ban and turning it into a shop is the last hope for more than 600 members, said president Don Lee.
If members of the Shipley Area Planning Panel back their officers' recommendations, it could spell last orders for the once-thriving club.
A Save Our Club petition has been signed by 127 people and a similar petition on Facebook has attracted support from 389 others. Shipley MP Philip Davies, whose constituency includes Bingley, has also sent a letter of support to the Council.
However, a report to the planning committee states the shop should be turned down because it would be outside Bingley town centre and it would"have an impact on the vitality and viability" of the main shopping area.
The committee will discuss the application, put in by Warrior Developments, at Shipley Town Hall next Thursday.
Mr Lee, 51, said: "We've been here for more than 100 years and the buyer who has put in the application is the only person who is going to keep the club open. It all depends on this application.
"The smoking ban has had a massive effect on our membership and, if this is refused, it will mean there is nowhere for the older people to go. You are not going to get 60 and 70-year-olds walking down town with all the yobs about on a night. It will leave them grounded."
Mr Lee said planning officers would be showing"terrible double standards" if they approved an application by Tesco to build a superstore in Bingley, which is being considered by Bradford Council. That application is to build a 40,000 sq ft store on the former Auction Mart - another out-of-town location.