Japan began its exploration in legal aid after World War II and it is one of the countries that establish legal aid system in the early days. Legal aid law，as an important part of the judicial reform in Japan，prescribe the operation of legal aid system systematically. 2016 witnessed a major revision on criminal procedure law and legal aid law take advantage of this chance，filling the gaps and expanding the coverage scope in civil cases. China and Japan share some similarities in culture. Therefore，the Japan legal aid reform could benefit its Chinese counterparts to some extent.