This paper aims to investigate the protection of foreign investors in Indonesia and Japan's investment Law. This study applies the normative legal research method with a qualitative approach to examine Indonesia and Japanese investment law. After reviewing relevant literature, this study found that Indonesia and Japan have developed economic agreement partnerships to safeguard investor rights. Indonesia also has a regulated mechanism to resolve the dispute between investors and host countries. Both countries provide incentives to encourage investment for economic growth and development. Nonetheless, Indonesia has six forbidden sectors for foreign investors, while Japan does not. Japan only has restricted sectors, namely mining, domestic shipping, broadcasting, radio, telecommunication, consigned freight forwarding, and aviation.