Not intended to promote violence, Smash aims to help people deal with the pressures of living in big cities like Beijing, Jin said, adding that their target customers are between 20 and 35 years old.
Another customer, Liu Chao, 32, looked relaxed and pleased after his session.
"If you have money, you can smash anything — smash some TVs, computers, wine bottles, furniture, mannequins, but the only thing you can't do is to smash someone," said Liu.
Similar ventures already exist in other countries, including the US.
Jin said around 600 people visit Smash each month.
"A woman brought all her wedding photos here, and she smashed them all. We welcome people to bring their own stuff," Jin said.
"Every time when we come across cases like this, they affirm our belief that we've provided a safe place to let out negative energy. And we are happy for that."
In Beijing, Jin said her next step is to open a new anger room in a shopping mall where people can take a break from their shopping to smash a bottle or two.