The hit Netflix series has inspired an array of costumes, which included guards, contestants and a killer robotic doll.
A heavy police presence in the area was maintained as revellers were asked to observe social-distancing rules as part of Hong Kong's zero-COVID policy.
Hong Kong has some of the most stringent travel restrictions in the world and is virtually COVID-19 free.
Due to the coronavirus situation being stable, revellers say this year's Halloween celebrations were bigger than last years.
"After panicking for so long, everyone can come out and have fun", said Halloween partygoer Jackie Tam who dressed as a guard from "Squid Game."