Revellers roamed the streets of the Lan Kwai Fong area wearing costumes, while bars dressed their storefronts with Halloween decorations.
Police patrolled the area carrying banners asking people to avoid gathering or crowding in one area.
The city's government eased social-distancing measures on Friday (October 30) with business hours of bars and clubs being extended to 2am, and the seating capacity of restaurants, pubs and nightclubs increasing to 75 per cent.
The relaxation of measures comes as the Asian financial hub has maintained single digit or no new local cases in recent weeks. However, the city has continued to register imported cases of the virus.