As an important and fundamental scientific research resource, laboratory animals have become an important tool for the continuous development of life exploration, medical research, drug development, and other fields. With the development of laws and regulations on the welfare of laboratory animals, the welfare of laboratory animals is increasingly valued by the international community and research communities. In order to maintain the welfare of laboratory animals, standardize the ethical review of laboratory animals and the behavior of laboratory animal practitioners, referring to advanced foreign experience and combining with the characteristics of ethical review of laboratory animal welfare in China, this article mainly outlines the review and approval process of animal use protocol, and the standards for evaluation. The aim is to provide reference for researchers in the writing of animal use protocol and for IACUC members in the ethical review of laboratory animal welfare.