There are many rules for ordinary naturalization – summary of requirements for acquiring Japanese citizenship


A foreigner must go through the naturalization procedure to obtain Japanese citizenship.

There are two types of naturalization: ordinary naturalization and simplified naturalization. Ordinary naturalization is the orthodox method of naturalization and requires the fulfillment of numerous conditions.

This article summarizes the requirements for acquiring Japanese citizenship through normal naturalization.


To obtain Japanese citizenship, you must have lived in Japan for at least five years.

Since you need to have lived in Japan continuously for at least 5 years, you do not meet the requirements if, for example, you lived in Japan for 3 years, lived abroad for 1 year, and then lived in Japan for 2 years.

Ability to act

A requirement for acquiring Japanese citizenship is that you must be over 18 years of age according to Japanese law.

You must also have the capacity to act (be of legal age) according to the laws of your own country.

For example, if the law of country A states that the age of majority is 20, an 18-year-old foreigner from country A does not meet the conditions for capacity to act.

Good behavior

Good behavior is also a prerequisite for acquiring Japanese citizenship.

Whether a person’s conduct can be considered good is judged comprehensively, taking into account the following factors in particular.

  • Do you have a criminal record, and if so, what is the criminal record?
  • Do you pay your taxes properly?
  • Are you a nuisance to society; for example, have you committed traffic violations?
  • Living conditions

To obtain Japanese citizenship, you must be able to live independently.

Even if your own income/ assets are insufficient, if your spouse’s income, relatives’ assets, etc. are sufficient to support you, you can meet this requirement.

Loss of original citizenship

As a prerequisite for acquiring Japanese citizenship, it is necessary to lose the citizenship of the country of origin.

For example, when a foreigner with citizenship A is naturalized in Japan, they must, in principle, give up their citizenship A.

However, if the person cannot voluntarily renounce their citizenship, this may be recognized as an exception.

Compliance with the Constitution

Compliance with the Japanese Constitution is also one of the conditions.

Specifically, the following two items are required.

  • You have not attempted to destroy the Japanese Constitution or the Japanese government by force, nor do you intend to do so.
  • You have never founded or joined a political party or other organization that pursues or demands any of the above goals.

Knowledge of the Japanese language

Your knowledge of the Japanese language may also be tested.

While there are no strict standards for the required level of Japanese language proficiency, generally level 3 proficiency on the Japanese Language Proficiency Test (3rd grade elementary school) is required.