Polytechnic University researchers say for the first time since 2012, students aged 12 to 18 had the lowest average happiness score among all age groups.
Dr Simon Lam, who conducted the study, said such a finding was rare even in other countries, as previous studies showed young people were generally happier than adults because they had fewer things to worry about.
Researchers invited 1,827 people last month to score their happiness on scale ranging from 0 to 10.
They found overall that Hong Kong people's happiness levels barely improved from last year, when the city was gripped by social unrest.
Respondents gave themselves an average score of 6.16, which is just 0.01 higher than last year’s figure.
Sylvia Chan from HK WeCare, which commissioned the study, said young people may have felt unhappy with the government and upset about disrupted schooling:
"I think because of Covid-19, the school suspensions contributed a lot [to] the emotion burden for students,” she said. “Students would think [they are] being locked up at home and cannot see their classmates and cannot go out and play – it can be one of the reasons that made them unhappy."
Female respondents were less happy overall than male respondents.
Researchers said that was a reversal of the usual trend where men normally scored lower on happiness than women, as they tended to be more repressed given stereotypical gender roles.
They said during the pandemic, women may have had to spend more time doing housework and taking care of children, and this may have increased the pressure on them.
The survey also found 46 percent of respondents showed signs of moderate to severe depression – around six percentage points higher than last year.
Researchers also asked respondents to rate their satisfaction with various external factors that could affect their happiness, such as government policy, the economy, living environment, the media, healthcare, and law and order.
They found that people gave the lowest scores to factors such as politics and society, government policy and trust in the government, while the city’s housing problems became less of a concern to many people.
They said the results showed that the government’s performance left a lot to be desired, adding that authorities should listen more to the people.
But researchers said even with unpleasant external factors, people could still strive to live a happier life through developing more positive values and caring more about society and others.