It's a style so ubiquitous that it's even earned a fond nickname: the "Beijing bikini."
But in a city in China's eastern Shandong province, Beijing bikini lovers -- and those who forgo tops altogether -- have fallen out of favor with the local authorities.
On Tuesday, authorities in Jinan -- a city of 8.7 million -- issued a notice ordering the public to keep their shirts on in public places. It came as temperatures rose to a sweltering 36C (96F) this week.
The sight of middle-aged men in China relaxing in public places with their shirt rolled up to expose their stomach, or going completely topless, is a common one throughout the country.
But Jinan authorities aim to rectify such "uncivilized behavior," according to the notice, which added that citizens had complained about the "uncivilized phenomenon" which damaged the image of the city.
Authorities said they planned to crack down on "improper dressing in public places," which included "shirtlessness" and "wanton exposure of body parts." Public bickering, jumping queues, littering, and "uncivilized dog walking" are also being targeted under the notice, which is aimed at enhancing the image of the city.
But on social media, many people thought the regulations were overkill.
"Being shirtless cuts more carbon emissions than turning on AC," one commenter said, while another added "Let the old people be free."
Resistance to Beijing bikini
It's not the first time that middle-aged Chinese men's proclivity for public toplessness in summer has fallen foul of the authorities.
In Tianjin -- a coastal city near Beijing -- a man was fined around $7 in May for shopping shirtless in a supermarket, according to the Tianjin police. The city introduced a regulation banning going topless earlier this year.
In Handan, in Hebei, the province that rings the capital, the government is so serious about men wearing tops in public that it has launched a campaign, that includes an educational mini-film, which shows a woman introducing her boyfriend to her topless father who is playing cards with his friends at a public park. But the boyfriend is offended by her father's state of undress, and pulls her aside to ask "Is that your dad? He's so uncivilized."
After a series of similar encounters, the man ultimately opts to wear a shirt and hat outside.