All of them allegedly took part in an unauthorised march and were involved in clashes with the police in Admiralty on Sunday.
Half of the defendants are students, two of whom are aged 14. The rest included a doctor, a nurse, a teacher, a social worker and an engineer.
Separately, the secretary general of Hong Kong Social Workers’ General Union also appeared at the court for assaulting the police.
A long queue was seen outside the court as the defendants’ families and supporters arrived for the hearing.