Officers raided a hotel last week and found the group managing the online shopping site Taobao using dozens of computers and other devices. The group, including six women, also received undisclosed cash fines.
Tourist visas do not allow visitors to engage in commercial activities.
Chinese visitors account for the highest number foreign arrivals in Vietnam. Nearly 3.6 million Chinese have visited Vietnam so far this year, up 45% from a year ago and accounting for nearly a third of all foreign arrivals.