We endeavour to provide a novel theory to evaluate environmental comfort level. A method that fuses multidimensional environmental parameters based on radar chart representation theory is provided in this paper. The value of the parameters is transformed into the linguistic description according to linear and nonlinear membership creation method. Consequently, an integrated and objective description about environmental comfort level is given. A measuring and testing system of indoor environmental comfort level is designed here by MSP430 MCU. The design is given and better performance is achieved. It is our belief that this method can be used in many other areas, where the quantitative and qualitative information transform is needed