The study investigated Chinese secondary school teachers' views on ethicality of teachers' practices in classroom assessment. Participants included 1,871 teachers from 205 secondary schools in 23 provinces, 4 municipalities, and 4 autonomous regions in China. A survey study with 14 authentic assessment scenarios revealed that there is no evident consensus on ethicality of teachers' practices in classroom assessment among the participant teachers, and discrepancies exist between teachers' views and the views of assessment professionals in the literature. Chinese secondary school teachers reported low agreement with the literature in assessment confidentiality, communication about grading, grading practice, and test administration. Gender and subject taught are significantly associated with teachers' ethical perceptions. The findings suggest that ethical issues in classroom assessment are complicated, and they are often interwoven with other factors including cultural background, educational policy, and institutional guidelines in assessments. The study findings are informative for the development of secondary school teacher education program, teachers' professional learning, and educational policy making.