Chris Brodman's friends told News 6 that Brodman died Sunday morning while visiting Tampa.
They have been posting tributes on social media since Sunday, saying that he passed away while attending a birthday party, News 6 reported.
The Hillsborough County Sheriff's Office said that it responded to a home around 1.50am Sunday after receiving reports about an unconscious man.
Authorities have not released any information about the man who died, pending notification of his family.
Brodman's boyfriend posted on Facebook: 'I still can't believe my baby is gone. I can't sleep I can't breathe I don't know how I'm going to go on without him.'
Orlando Torres, who also survived the mass shooting, told News 6 that he was first notified through Brodman's boyfriend that he had passed away.
'It was supposed to be a fun night. They were supposed to go out there and just, you know have a fun night out there in Tampa,' Torres told the station.
'His boyfriend posted on Facebook as well as my friend posted on Facebook that Chris Brodman had passed away.'
Torres said that Brodman was given a second chance at life, only to have his life cut short three months after the Pulse shooting.
'It's unfortunate this had to happen to someone that is just so sweet and nice and didn't deserve it, like anybody else,' said Torres.