The Joiners Arms, in Hackney Road, east London, shut in 2015.
Regal Homes, which wants to build nine flats on the site, incorporating a bar, has agreed to the planning condition, believed to be the first of its kind.
Tower Hamlets Council imposed the condition after the area lost 73% of its LGBT venues since 2006.
The Joiners Arms originally opened as an LGBT venue in 1997 and included fashion designer Alexander McQueen among its customers.
Regal Homes, which bought the site in 2014 - a year before the pub closed - has said it will give an LGBT operator first refusal on a 12-year lease for a new bar.
It added the redevelopment was expected to create 1,073 jobs.
The council has been working with Amy LamÃ©, the mayor of London's "Night Czar", on how to bring back a LGBT venue to Hackney Road.
In the application she says protecting LGBT venues is a "key part" of boosting London's "night-time economy".
"They contribute to London's economy, generate stronger and more resilient communities and are vital for many people's freedom of expression," she said.
"London has lost a quarter of its pubs and half of its nightclubs over the last 10 years."
She added a University College of London report showed the capital had lost 58% of its LGBT venues over the past decade, while Tower Hamlets had lost slightly more.
The czar said the report specifically cited the closure of The Joiner's Arms as one of several high-profile LGBT venues to shut in recent years.
The development is expected to be given the go ahead at a meeting of the council's planning committee on Wednesday.
John Biggs, mayor of Tower Hamlets, added: "Tower Hamlets Council is committed to celebrating our great diversity, which includes serving the needs of our LGBT+ community.
"I am delighted that as a council we are leading the way in using innovative ways to protect spaces such as the Joiners Arms site."

The Chinese firm said it was pursuing its South Korean rival in two courts - one in California, the other in Shenzhen.
According to Huawei, several of its cellular communications and software inventions had been used in Samsung's phones without its permission.
Samsung told the BBC it would defend its business interests.
The specific patents involved have not been disclosed.
However, Huawei has said at least some of them are classed as Frand - an acronym referring to "fair, reasonable and non-discriminatory".
This means the Chinese company has committed itself to offering anyone a licence so long as they agree to a non-excessive compensation.
This kind of agreement is common in the tech sector as it makes it possible for different companies' products to communicate and share data formats with each other.
Huawei's intellectual property chief indicated it was seeking permission to use some of Samsung's technologies in return rather than seeking a payment.
"Thus far, we have signed cross-licensing agreements with dozens of our competitors," said Ding Jianxing.
"We hope Samsung will respect Huawei's R&D investment and patents, stop infringing our patents and get the necessary licence from Huawei, and work together with Huawei to jointly drive the industry forward."
A Samsung spokesperson responded in an email to the BBC saying "we will thoroughly review the complaint and take appropriate action to defend Samsung's business interests".
The action comes at a time when Oracle and Google are waiting for a jury to come back with a verdict in a copyright trial that has pitted the two giants against each other in the US.
But such clashes have become less common since Apple and Samsung's high-profile courtroom battle in 2011, which led to both firms revealing secrets about their inner workings and racking up large legal bills.
One expert noted that just because papers had been filed in the latest case did not mean Huawei and Samsung would necessarily fight a similar battle in public.
"Huawei may have initiated litigation as lever to get a settlement," commented Ilya Kazi from the Chartered Institute of Patent Attorneys.
"We don't know if it intends to go all the way through. Most cases do settle."
Council officials have insisted a redevelopment of a former gay pub in London still includes an LGBT venue for the plans to go ahead.
[NEXT_CONCEPT]
Huawei is suing its tech rival Samsung over claims that its patents have been infringed.