As countries around the world put forward their respective big data strategies，big data has become a fundamental national strategic resource and a basic factor of production in society. Meanwhile，the issue of big data security is becoming increasingly prominent，with big data security incidents emerging frequently. Against this backdrop，different countries and regions are introducing policies on privacy security，data security and personal information protection in the field of big data. This article focuses on case study and literature research to comprehensively analyze the big data security systems internationally in 2019 and compare them with the system development in China. Trough analysis and study，it summarizes the good practices and results of advanced countries and regions and also identifies the gaps between our system and their systems，as well as the weaknesses in our system. On this basis，it draws on the experience and inspirations of other countries，in the hope of offering some valuable reference for the big data security system building in China.