# 民法 / Civil Code — 第七百九十一条 (Article 791) - Law: 民法 (Civil Code), 明治二十九年法律第八十九号 - English title "Civil Code": Ministry of Justice translation - Kind: Act — the distinction between 法律 (Act), 政令 (Cabinet Order), 省令 (Ministerial Order) and 条例 (local ordinance) decides who may issue it and what it may say. - Provision: 第七百九十一条 (Article 791)（子の氏の変更） — address `art-791` - Text in force since: 2026-06-24 - URL (the page that opens at this provision): https://japanlaw.org/ja/civil-code/art-791 - Permanent URL (e-Gov law ID, never renamed): https://japanlaw.org/l/129AC0000000089/art-791 - Every provision below carries its address and both URLs on the line under it. - Japanese text: e-Gov 法令検索, Digital Agency (デジタル庁). English: as marked on each line below. Only the Japanese as published by the government has legal effect; the text below is a copy of it. Every English rendering below is a translation and says which kind: the Ministry of Justice's translation, or this site's machine translation, whose model and date the Sources list names. They are never merged and never substituted for one another. --- ### 第七百九十一条（子の氏の変更） — (Changing a Child's Surname) caption: Ministry of Justice translation — Japanese Law Translation Database System art-791 · https://japanlaw.org/ja/civil-code/art-791 · https://japanlaw.org/l/129AC0000000089/art-791 **第一項** 子が父又は母と氏を異にする場合には、子は、家庭裁判所の許可を得て、戸籍法の定めるところにより届け出ることによって、その父又は母の氏を称することができる。 art-791/par-1 · https://japanlaw.org/ja/civil-code/art-791/par-1 · https://japanlaw.org/l/129AC0000000089/art-791/par-1 If a child's surname differs from that of the father or mother, the child may take the surname of the father or mother after obtaining the permission of the family court, through the filing of a registration pursuant to the provisions of the Family Register Act. Ministry of Justice translation — Japanese Law Translation Database System **第二項** 父又は母が氏を改めたことにより子が父母と氏を異にする場合には、子は、父母の婚姻中に限り、前項の許可を得ないで、戸籍法の定めるところにより届け出ることによって、その父母の氏を称することができる。 art-791/par-2 · https://japanlaw.org/ja/civil-code/art-791/par-2 · https://japanlaw.org/l/129AC0000000089/art-791/par-2 If a child's surname differs from that of the parents due to the father or mother changing surnames, the child may take the name of the parents without obtaining the permission referred to in the preceding paragraph only if the parents are married to each other, through the filing of a notification pursuant to the provisions of the Family Register Act. Ministry of Justice translation — Japanese Law Translation Database System **第三項** 子が十五歳未満であるときは、その法定代理人が、これに代わって、前二項の行為をすることができる。 art-791/par-3 · https://japanlaw.org/ja/civil-code/art-791/par-3 · https://japanlaw.org/l/129AC0000000089/art-791/par-3 If a child is under 15 years of age, the legal representative thereof may perform the acts referred to in the preceding two paragraphs on the child's behalf. Ministry of Justice translation — Japanese Law Translation Database System **第四項** 前三項の規定により氏を改めた未成年の子は、成年に達した時から一年以内に戸籍法の定めるところにより届け出ることによって、従前の氏に復することができる。 art-791/par-4 · https://japanlaw.org/ja/civil-code/art-791/par-4 · https://japanlaw.org/l/129AC0000000089/art-791/par-4 A minor who has changed surnames pursuant to the provisions of one of the preceding three paragraphs may revert to the previous surname within one year of attaining majority, through the filing of a notification pursuant to the provisions of the Family Register Act. Ministry of Justice translation — Japanese Law Translation Database System --- ## Cites - art-791/par-2: 前項 → 民法 第七百九十一条第一項 (Article 791, paragraph (1)), art-791/par-1 — https://japanlaw.org/ja/civil-code/art-791/par-1 · https://japanlaw.org/l/129AC0000000089/art-791/par-1 - art-791/par-3: 前二項 → 民法 第七百九十一条第一項 (Article 791, paragraph (1)), art-791/par-1 — https://japanlaw.org/ja/civil-code/art-791/par-1 · https://japanlaw.org/l/129AC0000000089/art-791/par-1 - art-791/par-3: 前二項 → 民法 第七百九十一条第二項 (Article 791, paragraph (2)), art-791/par-2 — https://japanlaw.org/ja/civil-code/art-791/par-2 · https://japanlaw.org/l/129AC0000000089/art-791/par-2 - art-791/par-4: 前三項 → 民法 第七百九十一条第一項 (Article 791, paragraph (1)), art-791/par-1 — https://japanlaw.org/ja/civil-code/art-791/par-1 · https://japanlaw.org/l/129AC0000000089/art-791/par-1 - art-791/par-4: 前三項 → 民法 第七百九十一条第二項 (Article 791, paragraph (2)), art-791/par-2 — https://japanlaw.org/ja/civil-code/art-791/par-2 · https://japanlaw.org/l/129AC0000000089/art-791/par-2 - art-791/par-4: 前三項 → 民法 第七百九十一条第三項 (Article 791, paragraph (3)), art-791/par-3 — https://japanlaw.org/ja/civil-code/art-791/par-3 · https://japanlaw.org/l/129AC0000000089/art-791/par-3 ## Cited by 7 provisions cite this one. No official source publishes this direction. - 戸籍法 第十九条第二項 — https://japanlaw.org/ja/family-register-act/art-19/par-2 · https://japanlaw.org/l/322AC0000000224/art-19/par-2 - 戸籍法 第九十八条第一項 — https://japanlaw.org/ja/family-register-act/art-98/par-1 · https://japanlaw.org/l/322AC0000000224/art-98/par-1 - 戸籍法 第九十八条第二項 — https://japanlaw.org/ja/family-register-act/art-98/par-2 · https://japanlaw.org/l/322AC0000000224/art-98/par-2 - 戸籍法 第九十九条第一項 — https://japanlaw.org/ja/family-register-act/art-99/par-1 · https://japanlaw.org/l/322AC0000000224/art-99/par-1 - 民法 第七百九十一条第二項（子の氏の変更） — https://japanlaw.org/ja/civil-code/art-791/par-2 · https://japanlaw.org/l/129AC0000000089/art-791/par-2 - 民法 第七百九十一条第三項（子の氏の変更） — https://japanlaw.org/ja/civil-code/art-791/par-3 · https://japanlaw.org/l/129AC0000000089/art-791/par-3 - 民法 第七百九十一条第四項（子の氏の変更） — https://japanlaw.org/ja/civil-code/art-791/par-4 · https://japanlaw.org/l/129AC0000000089/art-791/par-4 --- ## Sources - e-Gov 法令検索, Digital Agency (デジタル庁) — 民法 — the text in force from 2026-06-24 (https://laws.e-gov.go.jp/law/129AC0000000089/20260624_508AC0000000045), retrieved 2026-10-11 - Japanese Law Translation Database System, Ministry of Justice (法務省) — Civil Code — Ministry of Justice translation (part 2 of 2) (https://www.japaneselawtranslation.go.jp/en/laws/view/4275/tb), retrieved 2026-10-11 - Japanese Law Translation Database System, Ministry of Justice (法務省) — Civil Code — Ministry of Justice translation (part 1 of 2) (https://www.japaneselawtranslation.go.jp/en/laws/view/4848/tb), retrieved 2026-10-11 - This site's parser, version 190 — 民法 — structure, counts, cross-references and defined terms, computed 2026-10-11