Dozens of fire fighters are at the scene and video footage shows them on the roof as the smoke rises high into the New York sky.
The fire appears to have started on the roof, with the fire fighters seen dealing with the reported problem.
There have been no injuries or evacuations reported and the fire is under control, according to US outlet NBC News.
Donald Trump and his family are currently not in their residence inside the Fifth Street skyscraper.
Numerous social media uploads show the white smoke emerging from Trump Tower from different angles across New York.
Watch live webcam footage as firefighters deal with the reported fire at Trump Tower.
Emergency services were called to Trump Tower at around 7.20 local time, on Monday morning.
The fire appeared to break out in the building’s heating and cooling system, according to the FDNY.
The fire was quickly dealt with but firefighters remain on the scene to ensure the blaze didn’t spread to other locations.