METRO Police said the deadly crash happened just before 8 p.m. on the purple line on Fannin Street at Capitol Street.
Paramedics pronounced the victim dead at the scene.
Officials said the victim had been on the platform for an extended period of time before the crash.
It's unclear what led up to the deady crash. Police did not identify the victim.
Shuttle buses replaced the purple line temporarily after the crash, but regular service has since resumed.