This is the painful moment a woman was knocked over by a car park barrier that closed on her head.

Street surveillance cameras captured the moment the woman rode her bike straight into the descending gate arm in Foshan, in Guangdong, China, on Saturday, March 23.

Seemingly wanting to dodge the incoming riders in the bike lane, she went around them onto the main street and passed by a white sedan that drove under the raised barrier arm just seconds earlier.

But she did not realise the arm was already being lowered as she was about to pass under it.

Despite a security guard attempting to get the arm back up at the last minute, she rammed it head-first and fell off her bike.

Several riders stopped as she landed on the tarmac, then sat holding her forehead with her hand in apparent pain.

According to witnesses, the woman was later to a nearby hospital, although no serious injuries have been reported.