Sarayut Tanthien, chief of the park, said the signs were put up after some Chinese tourists were found collecting reefs from the beach at the Thalae Waek or the beach that connects small islands in the park.
He said several Chinese tourists were fined for their action.
The signs were put up in Thai, Chinese and English.
Sarayut and park officials inspected the Thalaewaek beach observe tourists’ behavior Tuesday.