Foreign nationals in possession of a valid passport and Residence Card who will be re-entering Japan within 1 year of their departure to continue their activities in Japan will, in principle, not be required to apply for a re-entry permit. This is called a special re-entry permit. 

Foreign nationals who have departed from Japan on a special re-entry permit will not be able to extend that permit while abroad.

Please note that such foreign nationals will lose their resident status if they fail to re-enter Japan within 1 year of their departure.

If your period of stay expires within 1 year after your departure, please ensure that you re-enter Japan before the expiration of your period of stay.

Note: You must submit an “International Travel Form (Study Abroad, Temporary return to home country, etc.)” whenever you leave Japan, whether classes are in session or not.

[References] Notice to international students returning to their country temporarily during vacation (PDF) 

※Click here for information on quarantine procedures on entry into Japan.
※Upon your arrival, you are required to submit the “Report form when you enter Japan（入国者報告フォーム）” to inform the university of your immigration status and health condition.