EMS crews responded to the scene at Borough Hall around 3:30 p.m. and the commuter was treated at the scene.
Officials say a 10 x 10 section fell 25 feet, hitting the man in his shoulder and causing minor injuries.
A shower of plaster and tiles shattered onto the platform, disrupting the evening commute. MTA crews cleared bags of it after poking at the ceiling to make sure riders below were safe.
It is one of the busiest stations in the system, and also one of the oldest.
"It's like stepping back in time," said rider Sean Kiley. "When I come onto the subway I can picture that this all looked very nice in 1960, 1970."
Kiley, from Ireland, has been in New York for about a year. He says the city's subway system stands out and not in a good way.
"I've been to London a lot and I can see the comparison," he said. "The tube in London compared to the subway in New York, it's just a better quality. It badly needs investment."
"This just reinforces my desire to get the funding we need to totally modernize all of our stations," said Transit Authority President Andy Byford.
Byford has a plan to modernize the system. The problem is the price tag and how to pay for it.
Internal estimates say it'll cost $19 billion in the first five years alone.
Mayor Bill de Blasio wants a new revenue source identified by the state. Governor Cuomo who controls the MTA, says he wants to pay for it through congestion pricing, a proposal that's hitting some road blocks in Albany.
"This incident just steels my resolve to get the money that New York City transit needs to modernize this system and to prevent this type of thing from happening," said Byford.
He said an initial survey shows the incident may have been caused by water damage.
Crews will survey the entire station overnight. It is not clear whether the work will impact the morning commute.
"We have structural engineers on site, we have operational people, and we're now assessing the status of the rest of that ceiling and what you can see the team doing downstairs now is they are deliberately poking the ceiling to bring down any remaining loose material," Byford said.
The incident caused delays on several subway lines, including the 2, 3, 4 and 5 trains.
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Bill and Sade, all of that ceramic tile came raining down on a rider this afternoon.
Lucky it didn't fall on his head.
And now the fear is... will the rest of this ceiling collapse?
Crews are trying to figure that out before the morning commute.