Nine people were given jail sentences of between 35 and 48 months on Saturday for rioting near the Polytechnic University during the 2019 social unrest.
The defendants are aged between 22 and 36.
District Court Judge Clement Lee said the riot lasted around 80 minutes, with some protesters throwing petrols bombs and blockading busy roads in Tsim Sha Tsui.
He said the group had acted violently towards the police and that a deterrent punishment was needed in order to protect the public interest and the personal safety of law enforcement officers.
He noted the defendants were good-natured but too enthusiastic about social affairs, and that they had let their passion overrule their rationality.
He expressed hope that the defendants would think about their future and work hard to better themselves.