The move comes amid concerns about the impact of Chinese online platforms on local markets due to their heavy discounting and the quality of goods available.
Nguyen Hoang Long, Vietnamese deputy trade minister, told a government meeting at the weekend that the ministry had worked with both Shein and Temu on the licensing matter.
"After the ministry's notification, if these platforms do not comply, the Ministry of Industry and Trade will coordinate with relevant agencies to implement technical measures such as blocking applications and domains," Long said in a government statement released after the meeting.
Fast-fashion retailer Shein has been selling into Vietnam for some time, while Temu, owned by Chinese e-commerce giant PDD Holdings started allowing users in Vietnam to shop last month.