# 民法 / Civil Code — 第六百四十四条 (Article 644) - 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: 第六百四十四条 (Article 644)（受任者の注意義務） — address `art-644` - Text in force since: 2026-06-24 - URL (the page that opens at this provision): https://japanlaw.org/en/civil-code/art-644 - Permanent URL (e-Gov law ID, never renamed): https://japanlaw.org/l/129AC0000000089/art-644 - 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. --- ### 第六百四十四条（受任者の注意義務） — (Duty of Care of Mandatary) caption: Ministry of Justice translation — Japanese Law Translation Database System art-644 · https://japanlaw.org/en/civil-code/art-644 · https://japanlaw.org/l/129AC0000000089/art-644 **第一項** 受任者は、委任の本旨に従い、善良な管理者の注意をもって、委任事務を処理する義務を負う。 art-644/par-1 · https://japanlaw.org/en/civil-code/art-644/par-1 · https://japanlaw.org/l/129AC0000000089/art-644/par-1 A mandatary bears a duty to administer the mandated business with the due care of a prudent manager in compliance with the main purpose of the mandate. Ministry of Justice translation — Japanese Law Translation Database System ## Cited by 9 provisions cite this one. No official source publishes this direction. - 会社法 第八百二十五条第七項（会社の財産に関する保全処分） — https://japanlaw.org/en/companies-act/art-825/par-7 · https://japanlaw.org/l/417AC0000000086/art-825/par-7 - 民法 第六百七十一条第一項（委任の規定の準用） — https://japanlaw.org/en/civil-code/art-671/par-1 · https://japanlaw.org/l/129AC0000000089/art-671/par-1 - 民法 第八百五十二条第一項（委任及び後見人の規定の準用） — https://japanlaw.org/en/civil-code/art-852/par-1 · https://japanlaw.org/l/129AC0000000089/art-852/par-1 - 民法 第八百六十九条第一項（委任及び親権の規定の準用） — https://japanlaw.org/en/civil-code/art-869/par-1 · https://japanlaw.org/l/129AC0000000089/art-869/par-1 - 民法 第八百七十六条の三第二項（保佐監督人） — https://japanlaw.org/en/civil-code/art-876-3/par-2 · https://japanlaw.org/l/129AC0000000089/art-876-3/par-2 - 民法 第八百七十六条の五第二項（保佐の事務及び保佐人の任務の終了等） — https://japanlaw.org/en/civil-code/art-876-5/par-2 · https://japanlaw.org/l/129AC0000000089/art-876-5/par-2 - 民法 第八百七十六条の八第二項（補助監督人） — https://japanlaw.org/en/civil-code/art-876-8/par-2 · https://japanlaw.org/l/129AC0000000089/art-876-8/par-2 - 民法 第八百七十六条の十第一項（補助の事務及び補助人の任務の終了等） — https://japanlaw.org/en/civil-code/art-876-10/par-1 · https://japanlaw.org/l/129AC0000000089/art-876-10/par-1 - 民法 第千十二条第三項（遺言執行者の権利義務） — https://japanlaw.org/en/civil-code/art-1012/par-3 · https://japanlaw.org/l/129AC0000000089/art-1012/par-3 --- ## 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 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