The aim of this article is to define the actual construction of the Japanese pension system influenced by the economic and social challenges and implemented pension system reforms. In this article, the development of Japanese pension system reforms is analysed, as well as legal, economic, social environment is identified. Until recently, it was a common perception that Japan has managed economic success without worsening the income inequality and pension benefits, but since the economic recession in the 1990, the Japanese pension (...) system faces a new challenge. Moreover, the Japanese population is ageing rapidly (low birth rate, long life expectancy), therefore, ageing influences the entire society and requires more complex and pressing pension system reforms. Analysis of scientific literature, legal acts, documents, historical methods was used. It may be used as methodical literature studying the actual processes in the field of the pension system reforms in Asian countries. (shrink)