Sun sensed the surging popularity of the sport after Spring Festival this year.
"People around me have been talking about it as a phenomenon," he says.
So far, his club has gathered more than 500 members.
Sun hosts about three frisbee events in the city's Chaoyang district each week. About 20 participants join each event.
The low threshold for playing in terms of age limits and equipment have both helped fuel the popularity of frisbee in China, experts say.
Zhang Kun, a veteran player and organizer of frisbee events in Beijing, believes social media platforms and online influencers played a positive role in promoting the sport during the early days of the pandemic.
"People now think it is cool to play frisbee," Zhang says.
The sport is easy to pick up and understand, he adds.
"Your attention will be fixed on the flying disc once it is thrown and airborne, and you might feel you're flying too," Zhang says, adding that the experience is a great outlet for venting the pressures of fast-paced city life.