ISO 3166-2:JP is the entry for Japan in ISO 3166-2, part of the ISO 3166 standard published by the International Organization for Standardization (ISO), which defines codes for the names of the principal subdivisions (e.g., provinces or states) of all countries coded in ISO 3166-1.

Currently for Japan, ISO 3166-2 codes are defined for 47 prefectures.

Each code consists of two parts, separated by a hyphen. The first part is JP, the ISO 3166-1 alpha-2 code of Japan. The second part is two digits (01–47), which is the Japanese Industrial Standard JIS X 0401 code of the prefecture. The codes are assigned roughly from north to south.

Subdivision names are listed as in the ISO 3166-2 standard published by the ISO 3166 Maintenance Agency (ISO 3166/MA).

ISO 3166-2 is part of the ISO 3166 standard published by the International Organization for Standardization (ISO), and defines codes for the names of the principal subdivisions (e.g., provinces or states) of all countries coded in ISO 3166-1. The official name of the standard is Codes for the representation of names of countries and their subdivisions – Part 2: Country subdivision code. It was first published in 1998.

The purpose of ISO 3166-2 is to establish an international standard of short and unique alphanumeric codes to represent the relevant administrative divisions and dependent territories of all countries in a more convenient and less ambiguous form than their full names. Each complete ISO 3166-2 code consists of two parts, separated by a hyphen:

Each complete ISO 3166-2 code can then be used to uniquely identify a country subdivision in a global context.

Currently more than 4000 codes are defined in ISO 3166-2. For some countries, codes are defined for more than one level of subdivisions.