A train wheel came loose and landed on a taxi that was parked below a monorail track in Thailand.

Footage shows the detached wheel bouncing off the ground before landing on the cab of Wirat Khumsap, 73, as he was driving along Thepharak Road in Samut Prakan province on January 2.

The object smashed onto the taxi bonnet, startling Wirat who pulled over to inspect the damage. He and his passenger were uninjured.

Local media reported the Yellow Line service was still operational, and the damaged train was able to enter the Si Thepha Station after losing its wheel.

Authorities said an investigation into the incident was underway.

The mishap comes nine days after monorail power lines fell onto a road in Bangkok on December 24.

While in September last year, worried passengers clung on for their lives during a terror ride over Bangkok when a monorail's doors were jammed wide open.