The obligation of individual income tax is depending on your residential category.
<A> Residents (居住者)
 (1) except for non-permanent residents(非永住者以外の居住者)
 (2) non-permanent residents(非永住者)
<B> Non-Residents(非居住者)

<A> Residents (居住者)
Any individual who has a domicile or owns a residence continuously for one year or more is classified as a resident.(居住者とは日本国内に住所を有しまたは現在まで引き続いて1年以上居所がある個人をいいます。)

(1) except for non-permanent residents(非永住者以外の居住者)
Residents, except for those classified as “non-permanent residents” have an obligation to pay the income tax etc. for whole domestic source income and foreign source income.
(非永住者以外の居住者は日本国内で発生した所得だけでなく全世界の所得について日本の所得税の納税義務の対象となります。)

(2) non-permanent residents(非永住者)
Non-permanent residents are obliged to pay income tax etc. with respect to any income which has its sources in Japan, any income which has its sources abroad and is paid in this country and remitted from abroad.
(非永住者は国内源泉所得と、国外源泉所得で日本国内において支払われ又は日本国内に送金されたものについて課税されます)

Definition : “non-permanent residents”
Among residents, any individual of non Japanese nationality having domicile or residence in Japan for an aggregate period of five years or less within the last ten years is classified as a non-permanent resident.
(非永住者とは、居住者のうち日本国籍がなく、かつ、過去10年以内の間に日本国内に住所又は居所を有していた期間の合計が5年以下である個人をいいます)

<B> Non-Residents(非居住者)
Non-residents are obligated to pay the income tax etc.for any income from domestic sources. (非居住者とは居住者以外の個人をいい、日本の国内源泉所得について課税されます)

<INFORMATION>
English Services
Individual Income Tax : Salaries and Wages
Exemption for dependents, etc., for relatives living outside Japan