Although numbers dwindled dramatically at the city's main protest sites, many said they would return later in the day to resume their campaign for free elections, which has seen tens of thousands of people pour onto the streets.
The government was forced to shut its headquarters on Friday - leaving 3,000 civil servants at home - because of the massed ranks of protesters blocking the access roads. Hong Kong's embattled leader Leung Chun-ying had insisted the offices must reopen today, warning he would "take all necessary actions to restore social order".
I'm happy the protesters opened the barriers today: Female civil servant
In fear of a repeat of ugly scenes a week ago when police unleashed tear gas on the crowds, many departed, leaving a committed core of about a thousand who waged a vigil through the night. As dawn broke, a knot of protesters partially blocked the entrance to the complex with barricades, but kept a narrow section open to allow workers to pass through.
"I'm happy the protesters opened the barriers today," one female civil servant said as she pushed through. "I need to work!" The activists insisted their campaign was not losing steam after a week-long standoff that has at times erupted into violence.
"We're going to be here until we get a response from the government," said 20-year-old student Jurkin Wong who was sitting with friends as they woke from fitful slumber on the streets. "We have to stay here. It's for our future."
Two legislative meetings at the government offices were cancelled today but a government spokeswoman could not immediately give a reason. Handed back to Chinese rule in 1997, Hong Kong is governed under a "one country, two systems" deal that guarantees civil liberties not seen on the mainland, including freedom of speech and the right to protest.