Abstract: This article aims to analyze the beliefs of basic education teachers about grade retention. To that end, it discusses possible relations between beliefs about grade retention, beliefs about justice and evaluation principles, and teachers’ knowledge about the findings of research on the effects of grade retention. We also present teacher profile characteristics that can influence teacher adhesion to grade retention. The relationship between the beliefs mentioned, and between them and knowledge of research, was analyzed by correlation and the identification of characteristics associated with retention was done by regression analysis. We used primary data concerning almost 5.5 thousand teachers that teach Portuguese Language. We found that teachers who adhere to retention tend to also adhere to a meritocratic principle of justice and to normative assessment. Having more experience in teaching, not teaching in initial years of basic education, a greater knowledge of research of the subject, and holding a Master’s or a Ph. D. degree characterize the teachers who are less likely to agree with grade retention.