This report describes the development and validation of an instrument, the University Mathematics Classroom Environment Questionnaire (UMCEQ), for assessing the mathematics classroom environment in tertiary institutions in China. Through the use of multiple methods, including exploratory and confirmatory factor analyses, on two independent samples of 1,476 and 1,024 tertiary students, results show that the 48-item UMCEQ finalised in this study has a stable factor structure and good psychometric qualities, including reliability, discriminant validity and construct validity. The concurrent validity of the UMCEQ is also examined through its correlations with students' approaches to learning. These eight factors cover all three categories for conceptualising human environments, i.e. relationship, personal development and system maintenance and change. Four dimensions are suggested to understand the characteristics of classroom environment in Chinese tertiary institutions. The implications and suggestions for future research are finally put forward.