It happened around 3 a.m. on Gibson Street and Jackson Hill Street.
Firefighters found the man unconscious on the balcony of the townhome and pulled him to safety.
The fire was contained to the townhome, and no other injuries were reported.
The man was taken to a hospital, but there was no word on his condition.
Thursday's rescue was at least the second one in the city over the past 24 hours.
On Wednesday, Houston firefighters pulled a woman from a burning apartment in north Houston.