Foreigners can take the National Examination.
外国人又可以参加国家考試。

If you already have got the qualification as a nurse in other countries, you don't have to go to nurse-school in Japan. But you have to take the National Examination.
如果，在外国已経有資格，不用入学在日本「看護学校」。但是，要「看護師国家試験受験資格認定」的申請。

For details:詳細

【看護師国家試験の受験資格認定について】（厚生労働省）
外国の看護師学校養成所を卒業し、外国において看護師免許を取得した者が、日本で看護師国家試験を受験するためには、保健師助産師看護師法（昭和２３年法律第２０３号）第２１条第５号に基づき、厚生労働大臣の認定が必要とされている。平成27年度の受験資格認定の手続き及び審査方法は、以下の通りである。
http://www.mhlw.go.jp/kouseiroudoushou/shikaku_shiken/kangoshi/jukenshikaku.html
＊「平成27年」＝2015年

The procedure of National Examination:
第104回看護師国家試験実施要領 (The date of examination is February 22nd, 2015)
http://www.mhlw.go.jp/kouseiroudoushou/shikaku_shiken/kangoshi/

*If you don't have the qualification as a nurse, you have to enter nurse-school in Japan.
After you graduate high school, you enter nurse-school, and study 3 years,
and take the National Exam.
After you pass the exam, you become a nurse.

Books:
「看護・医療大学・短大・専門・各種学校ガイド」2016年度用
晶文社　\2000+tax
ISBN: 9784794998163

There's a lot of Scholarships for nurse-schools in Japan (most sponsors are hospitals).
You can apply free-tuiton programs.
http://www.kanngogakkou.com/shougakukin.html

* (several years ago:) I know the girl from Vietnam who used free-tuition program and enterd nurse-school in Tokyo.
The sponser was a hospital.
After she graduated nurse-school and passed the National exam,
she had the obligation to work for the hospital (for several years).
The hospital she (at that time) worked has a dormitory for nurses near their hospital,
and she lived at the dorm.
She was economically independent, worked for medical related job, and enjoyed city life on holidays.
It seems to me, it's not bad for young women from foreign countries who looks for the opportunities.

You can get both: National license and Bachelor's degree!
(*Japanese-Language Proficiency Test N2 level required: 要日本語能力試験２級)
International University of Health and Welfare at Narita Campus （国際医療福祉大学成田キャンパス）

http://www.iuhw.ac.jp/admission/outline/tokubetu_02.html

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