It happened shortly after 5 p.m., police said. When police arrived, they found the motorcyclist unresponsive. The car's driver, who was the only person in the sedan, was not injured.
The victim was identified as David Wayne Dunn, 57.
Reports said Dunn was traveling east on Seabrook Road when he collided with Mario Herreramendoza who was trying to make a left turn.
Seabrook Road was closed between Sylvester Street and Cross Link Road.
The crash is under investigation; no charges have been filed.