A group of fishing and boat company owners have been charged by a court in Taiwan for locking up 81 migrant workers to prevent them escaping.

19 people face charges of human trafficking and offences against personal liberty — and could receive a maximum seven-year jail sentence if convicted.

The fishermen were from countries including Vietnam, Tanzania, Indonesia and the Philippines.

The court heard that a number of the men were sometimes made to work for 48 consecutive hours without rest.

After a day out at sea, the fishing company owners would lock the workers in tiny windowless rooms to prevent them leaving the job.

The companies in question will be ordered to pay $US123,000 in back pay for the workers.

Taiwanese employers and recruitment companies have repeatedly come under fire for exploiting migrant workers, the majority of which come from Southeast Asian countries.