More than 900 candidates are competing for 431 seats in 18 district councils, where pro-Beijing parties currently hold a majority, at a time when people are divided over the pace of political reform.
The results, due late on Sunday, will provide insight into how a Legislative Council election due next year and a controversial leadership poll in 2017 could pan out.
The 79-day demonstrations last year, when activists streamed on to highways to demand full democracy for the former British colony, became the biggest political challenge to Beijing's Communist Party leaders in years.
The protests failed to persuade China to allow a fully democratic vote in 2017. Beijing says city voters have to chose from a list of candidates it has approved.
But they triggered what many in the financial centre see as a political awakening, which has included a lively debate over how much control China's central government should have.
"It feels like once the Umbrella Movement was over, we didn't know which way to go from there," said Steve Ng, a former chef who is running in the district council elections, referring to the democracy protests. "I wanted to see if I had the ability to continue to push the democratic movement."
Candidates have been lobbying hard across Hong Kong, although a wider choice of parties after last year's protests could make it harder for voters to decide at the polling booths.
The election will have a higher turnout than the 41.5 per cent witnessed in 2011, according to a poll by the University of Hong Kong.
Hong Kong returned to Chinese rule in 1997 under a "one country, two systems" formula that gives it substantial autonomy and freedoms, with universal suffrage promised as an "ultimate goal".
District councillors command little power, acting more in an advisory role in which they can push forward policies for the government to consider.
