Foreign students will not be allowed to stay in the US this autumn if their universities have moved classes fully online, unless they switch to a course with in-person tuition.
The US Immigration and Customs Enforcement (ICE) agency said people could face deportation if they do not comply with the rules.
Many universities are moving classes online due to the coronavirus pandemic.
It is not clear how many students will be affected.
Large numbers of foreign students travel to the US to study every year and are a significant source of revenue for universities as many pay full tuition.