This chapter explores the current status and practices of online privacy protection in Japan. Since the concept of privacy in Japan is different from that in western countries, the background of online privacy concepts and control mechanisms are discussed. The chapter then introduces Japan's Act on the Protection of Personal Information along with the privacy protection system in Japan. Following the discussion of the privacy law, Japan's privacy protection mechanisms to support and implement the new act are examined. To help companies make smooth adjustments and transitions, a four-stage privacy protection solution model is presented. Further, this chapter discusses two case studies to exemplify the problems and dilemmas encountered by two Japanese enterprises. The cases are analyzed and their implications are discussed. The chapter is concluded with future trends and research directions.