Are Roof Rats Legal in Japan? Keeping, Breeding & Selling

5 min read · Updated August 2026

Roof Rat Laws › Japan

Summary. In Japan, keeping and hobby-breeding a captive-bred roof rat is legal and unregulated federally: the species is deliberately NOT a ‘Specified Animal’ (特定動物, hazardous) and NOT a ‘Designated Invasive Alien Species’ (特定外来生物), a 2005 expert committee chose to exclude it because it’s too long-established to regulate. Commercial activity (breeding for profit, retail sale, exhibition, or large-scale free rehoming) triggers registration as a First-Class (or Second-Class) Animal Handling Business with facility/welfare standards. The big restriction is IMPORT: bringing a roof rat into Japan is de-facto prohibited for the public, the Ministry of Health requires imported rodents to have lived since birth in a foreign-government-designated biosecure facility (homes/hobby breeders don’t qualify). Never release one.

Not confirmed by the regulator. This page is based on our own desk research; the sources we used are listed below. Last reviewed 2026-06-07.
legal note This is a research aid, not legal advice; rules change and are interpreted by local officials. Verify with the official source before acting.

Status by activity

Keeping / owning   Legal

Confidence: High · Last verified 2026-06-07

Private possession needs no federal permit: R. rattus is not a ‘Specified Animal’ (特定動物, that list targets primates, big carnivores, large/venomous reptiles, not rodents), and it is not a ‘Designated Invasive Alien Species’ (特定外来生物). The 2005 Ministry of the Environment expert committee deliberately excluded it (long-established via maritime trade; eradication-vs-pet distinction). Domestic keeping is treated like keeping a fancy rat or guinea pig.

Sources: Japan Ministry of the Environment (MOE), Japan Ministry of the Environment (MOE), Japan Ministry of the Environment (MOE)

Breeding   Legal

Confidence: High · Last verified 2026-06-07

Private breeding without intent to profit/advertise/distribute commercially is entirely outside the commercial animal-handling law. (Commercial-scale breeding triggers First-Class Animal Handling Business registration, see sell_give.)

Sources: Japan Ministry of the Environment (MOE)

Selling or giving away   Legal with a permit

Confidence: High · Last verified 2026-06-07

Selling for profit (or breeding to sell) requires registration as a First-Class Animal Handling Business (第一種動物取扱業) with the prefecture, plus facility/caging/disclosure standards and an Animal Handling Manager. Giving animals away free to ‘a large number of unspecified people’ on a continuing basis requires Second-Class (第二種) notification. Occasional free rehoming to friends/family is unregulated.

Sources: Japan Ministry of the Environment (MOE), Japan Ministry of the Environment (MOE)

Transport & import   Restricted

Confidence: High · Last verified 2026-06-07

DOMESTIC transport between prefectures is unregulated (subject only to carrier policies). IMPORT is de-facto prohibited for pets: under the Infectious Diseases Control Law’s Animal Import Notification System, all live rodents need a health certificate from the EXPORTING government certifying the animal lived since birth in a government-designated disease-free facility, which homes and hobby breeders cannot obtain, so a pet roof rat cannot legally be imported. (R. rattus is not on the absolute-prohibition list, but the facility rule is an effective ban.) Export from Japan is legal with the destination country’s health certificate (MAFF AQS). Never release.

Sources: Japan Ministry of Health, Labour and Welfare (MHLW), Japan Ministry of Health, Labour and Welfare (MHLW)

Restrictions & responsibilities

Commercial selling/breeding (for profit) = First-Class Animal Handling Business registration (第一種動物取扱業) with the prefecture: facility floor plans, cleanable escape-resistant enclosures, space to ‘stand/lie/move’ naturally, an Animal Handling Manager, and written species/sex/origin disclosure at transfer. Large-scale non-commercial giveaway = Second-Class (第二種) notification (penalty up to ¥300,000 for failing to notify).
  • Register as a First-Class Animal Handling Business before any commercial sale/breeding
  • Or file a Second-Class notification for large-scale free rehoming

Where: Prefectural government (animal welfare center / public health dept)

Source: Japan Ministry of the Environment (MOE), Japan Ministry of the Environment (MOE)

Importing a roof rat into Japan is effectively impossible for pet owners: imported rodents need an exporting-government health certificate proving the animal lived since birth in a government-DESIGNATED biosecure facility (homes/hobby breeders can’t qualify). MHLW states such pets ‘basically cannot be brought into Japan.’

Where: Ministry of Health, Labour and Welfare (quarantine station at port of entry)

Source: Japan Ministry of Health, Labour and Welfare (MHLW), Japan Ministry of Health, Labour and Welfare (MHLW)

Thinking about keeping or breeding roof rats? Start with the care & husbandry guide, try the interactive games, or get in touch about joining as a colony keeper.

Official sources

Search terms: Rattus rattus, クマネズミ (kumanezumi), roof rat, black rat, ship rat.

About this page
Last reviewed 2026-06-07, which is when a person last read this page against its sources. Spotted an error, or know the law has changed? Email blonderoofrat@gmail.com. And if you write to the agency yourself and get an answer in writing, please forward it. Written agency replies are how 31 of these pages stopped being research and became confirmed.