Import regulations by Japan customs

Imports:

Alcoholic beverages 3 bottles Approximately 760 ml per bottle
Cigarettes 400 If a visitor brings in more than one kind of tobacco product then the total allowance is 500 g.
Cigars 100
Others (e.g. loose tobacco) 500g
Perfumes 2oz 1 oz is equivalent to approx. 28 cc.
(excluding eau de cologne and eau de toilette)
Other items 200,000yen The total overseas market value of all articles other than the above items must be under 200,000 yen. Any item whose overseas market value is under 10,000 yen is free of duty and/or tax and is not included in the calculation of the total overseas market value of all articles. There is no duty-free allowance for articles having a market value of more than 200,000 yen each or each set.

The quantity of pharmaceuticals and cosmetics, including both prescription and non-prescription drugs and some food supplements, including vitamin and mineral supplements, which a visitor can bring into Japan at one time may be limited.

Export regulations by Japan customs

Exports:
Prohibited items
Counterfeit, altered or imitated coins, paper money, banknotes or securities; all plants with soil; most meats and fruits (prohibited meats include eggs, bones, horns etc of cows, goats, sheep, bees, chickens, dogs, ducks, geese, horses, rabbits and turkeys); animals without health certificates; firearms and ammunition; narcotics; obscene articles and publications (including films)

Other Japan customs information

It is sometimes recommended to be vaccinated against typhoid.

Food drink: Food and drink are generally considered safe but there is risk of parasitic infection and toxins from raw seafood.

Other risks: Vaccination against Hepatitis A is sometimes recommended; hepatitis C also occurs. Typhus occurs in some river valleys. Japanese encephalitis may occur and paragonimiasis has been reported. TB occurs.

Health care: Health insurance is strongly recommended, owing to the high cost of treatment. The International Association for Medical Assistance to Travellers provides English-speaking doctors. There are hospitals in all major cities.

http://www.jnto.go.jp/eng/arrange/essential/customs.html