2025-06-14

The acquisition of Japanese citizenship by a foreigner is called naturalization. Basically, a person must be an adult (18 years old or older) to apply for naturalization, but if certain conditions are met, a minor can also apply for naturalization. We will explain in detail.

What is an application for naturalization?

Naturalization is the acquisition of Japanese nationality by a foreigner who has a status of residence in Japan. Since dual nationality is not allowed in Japan, once you become a Japanese citizen, you lose your current foreign nationality.

The following documents are required to apply for naturalization.

　・Application form for naturalization (a photograph of the applicant is required)

　・Documents describing the outline of the applicant’s relatives

　・Statement of reasons for naturalization

　・Resume

　・Documents outlining the applicant’s livelihood

　・Documents describing the outline of the applicant’s business

　・Copy of certificate of residence

　・Documents proving nationality

　・Documents proving kinship

　・Documents proving tax payment

　・Documents proving income

　・Documents proving residency history

Conditions for Naturalization

The following six conditions must be met in order for an application for naturalization to be approved.

The first is that the applicant must have a continuous domicile in Japan by the time of application for naturalization (address condition). However, even if the applicant has an address in Japan, this condition may not apply if the applicant has lived abroad for a long period of time during the five years prior to the application.

Second, the applicant must be at least 18 years old (ability requirement). In addition, the applicant must have reached the age of majority under the laws of his/her home country.

Third, the applicant must not be delinquent in paying taxes, have never been criminally convicted, or have never committed a serious traffic violation (the “good conduct” condition).

Fourth, the applicant must be able to live on the assets and skills of his or her spouse or other relatives with whom he or she shares a living (living conditions). In other words, it is advantageous if the applicant and his/her relatives have assets and the skills and qualifications to earn a living.

Fifth, the applicant must have no nationality or must agree to lose his/her current nationality by acquiring Japanese citizenship (condition to prevent dual nationality).

Sixth, the applicant must not have plotted or advocated the destruction of the Constitution of Japan or the government established under the Constitution by violence, or have formed or joined a political party or other organization with such objectives (Constitutional Compliance Condition).

Can a minor apply for naturalization?

As stated in the second of the previous conditions, the applicant must be of legal age. However, a minor may apply for naturalization in the following three cases.

The first is when applying for naturalization together with either parents. In this case, the age of the child is not required. If the child is under 15 years of age, the parent who is the legal representative must file the application on behalf of the child. If the child is between 15 and 18 years of age, the child himself/herself will be responsible for the naturalization application process, including the preparation of documents and interviews.

The second is when one of the parents is a Japanese citizen. In this case, the “capacity requirement,” “address requirement,” and “livelihood requirement” are relaxed.

The third is the case of a minor foreign national who is adopted by a Japanese national. However, please note that in this case, there is a condition that the applicant must “have continuously resided in Japan for at least one year.

Summary

Although being of legal age is a condition for applying for naturalization, if a parent has Japanese nationality, a minor can also apply. However, there are some conditions, so you need to be very careful when applying.