In this paper, the university teaching buildings in Chongqing are taken as study object, and the indoor thermal environment of classroom is studied with the ways of investigation and testing, in which the indoor thermal environment of classroom is characterized by two aspects: personal and impersonal. The accepted thermal environment range of the classroom in summer is obtained. The difference between predicted thermal sensation and measured one as well as the influence of air velocity on thermal sensation are analyzed. Some measures to improve indoor thermal quality are proposed.