In a statement, the association cited a number of cases during Sunday’s protests in which it said “officers attacked journalists for no reason”.
It said some journalists were pushed to the ground or pepper sprayed, while others had their cameras and mobile phones snatched by police officers.
The association also dismissed an explanation given by a police spokesman, who said journalists in Mong Kok were pepper sprayed accidentally because the situation was chaotic.
It said the explanation didn’t match the facts, which clearly demonstrate that officers had deliberately targeted the journalists.
A reporter from RTHK was among those hit by the pepper spray in Mong Kok and went to hospital for treatment.
The public broadcaster urged the police to respect media freedom and asked management to restrain frontline officers.