Scientific evaluation in China is going through a transition period. In dealing with the misuse and alienation of quantitative indicators, China had initiated a top-down reform. To help better understand the scientific evaluation policy in China and provide reference for further reform, this study investigated the evolution and characteristics of scientific evaluation in China from a bibliometric perspective. In total, 343 policy documents from 1978 to 2021 were collected. Based on the temporal distribution of policy documents and timeline of landmark policy documents, four phases were identified. Text mining technique and social network analysis were used to identify the shift of policy focus over different phases. The four phases were characterized from three aspects: (1) The time span and number of relevant policy documents; (2) The focus of policy document content; and (3) The collaborative network of ministries that release the policy documents.