In this paper, the overall comfort of humans in thermal, light, acoustic and air quality environments was studied in a university classroom in Shanghai, and the actual overall comfort vote index was evaluated. The dimensionless function of each environmental evaluation index and human comfort level was established by a combination of subjective questionnaire assessment and objective parameter measurement, and the weight of each environmental evaluation index was obtained by the method of vector similarity. The overall comfort evaluation model was synthesized by using the punishment substitution method, dimensionless function and weight. The influence of different environmental combinations on the overall comfort evaluation model was explored, and the results indicated that the more a single evaluation index deviated from its comfort zone, the more obvious the change it caused in comprehensive comfort. The model can be used to adjust classroom environmental parameters to improve comprehensive comfort, and the results should provide a reference for evaluating the overall comfort of the classroom environment and a reasonable basis for classroom environment design parameters.