International students coming to study and research at universities are assigned the status of residence "Student （ryugaku）", and working is not permitted under this status. Students must apply for and obtain Permission to Engage in Activity other than that Permitted under the Status of Residence Previously Granted to engage even in part-time work.
Those who work without this permission will be subject to punishment or deportation from Japan. It is also forbidden to work at any adult-entertainment business.
After you find work, you need to apply for a permit. To start working before you obtain this permit is illegal. Please be sure to obtain permit before starting to work.
Please refer to the page : "Part-time Jobs"as well.
［Items required for application］
［1］ Application for Permission to Engage in Activity Other Than That Permitted under the Status of Residence Previously Granted（http://www.immi-moj.go.jp/english/tetuduki/kanri/shyorui/09.html）
*Currently forms are not downloadable at MOJ's website. Please find "PDF" or "Excel" at the Japanese ver. website http://www.moj.go.jp/ONLINE/IMMIGRATION/16-8.html (May 2019)
［2］ Residence card
・ Please ensure you keep your qualification for residence as "Student（ ryugaku）" during your stay.
・ International students of UTokyo who will be working as Research Assistants or Teaching Assistants at the University please confirm with your departmental office whether or not the permit is required.
・ Be sure to notify the administrative office of your faculty or graduate school when you receive the work permit to do a part-time job.
・ International students are limited to 28 hours of part-time work per week, and 8 hours a day during summer or winter breaks. For the academic calendar for your school/department, please contact your academic office.
Ref: University-wide standard academic calendar https://www.u-tokyo.ac.jp/en/current-students/university_calendar.html
・ Part-time work is not permitted during leaves of absence from the university.
・ The spouse of an international student residing in Japan as a dependent is required to obtain the similar type of work permit if he or she wishes to engage in part-time work.