Most automated teller machines (ATMs) in Japan do not accept credit, debit or ATM cards issued outside of Japan.
The big exception are the ATMs found at the over 21,000 post offices and at 13,000 Seven Bank ATMs throughout the country.
ATMs at Post offices are available for this service, but only for those cards the sticker indicates.
These ATMs at post office allow you to withdraw cash by foreign Visa, Plus, MasterCard, Euro card, Maestro, Cirrus, American Express, Diners and JCB cards and provide an English user menu.
ATMs at major post offices are typically available weekdays from 7:00 to 21:00 and closed on weekends, some may also open on Saturdays and Sundays.
In addition to the ATMs at post offices, small number of international ATMs are located in major department stores, airports and Citibank branches.
In order to use international ATMs, make sure that your credit or debit card can be used abroad and that you know its PIN before leaving for Japan.
SevenBank accepts Visa, Plus, Master card, Euro card, Maestro, Cirrus, American Express, Diners,JCB card and China UnionPay.
ATMs for Seven Bank can be found at Seven-Eleven convenience stores nationwide, and nearly all are conveniently accessible 24 hours a day.
Also, check what fees and daily and/or monthly limits are associated with international withdraws.
Seven bank http://www.sevenbank.co.jp/english/