In the practice of laboratory animal ethics and welfare, 3R is the core of contents. As the subject in this process, individuals working in laboratory animal field play a leading role and should take corresponding responsibility. In this article, the author discussed the function, realized route, and significance of subject responsibility in the practice of laboratory animal ethics and welfare by following aspects: proposal of subject responsibility, requirements of responsibility in the implementation of ethics and welfare regulation, in the application of ethics and welfare technique and method, in the development of ethics and welfare products, in the management and monitoring of ethics and welfare application, as well as establishing an anniversary and cenotaphs to embody subject responsibility.