Can he go to hongkong as a tourist again? he overstayed in mainland china.

hi! my friend overstayed in mainland China for 11months..and back to his country. now,he and his family are planning to have vacation in Hongkong for a week.. can he go to hongkong as a tourist again? he overstayed in mainland china.. he didnt bother to ask the PSB officers about this.. thank you!