Police say the cab collided with the motorcycle at 125th Street and Lenox Avenue in Harlem, sending the bike into the bus carrying tourists.
A group of Marines standing nearby came to the man's aid until EMS workers arrived on the scene.
He died at the hospital.
The victim has been identified as 53-year old Juan Velez of Mount Vernon.
Tourists on the bus were shaken up by the incident.
No one on the bus was hurt.
Police are still investigating the cause of the crash.
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