Employees are sometimes the most dangerous competitors of an enterprise because they can gain access to the business secrets of that business and bring it to the service of a competitor or do business on their own to compete with a former employer. Non-compete agreements are considered as one of the effective tools to prevent such behavior. In Vietnam, the issue of non-compete agreements in labor relations has not been directly regulated by law. Meanwhile, this issue has been more specifically regulated in Japanese law. With certain similarities in culture, society, and law between the two countries, the author uses the comparative law method to analyze the provisions of Japanese law and the current situation of Vietnamese law on non-compete agreements in labor relations. Lessons learned from the research will help perfect the law of Vietnam in the coming time.