Abstract: A fuzzy system is the mapping relationship obtaining the input and output of the response by measuring the data or digital sensors, although it does not depend on the precise mathematical model, with the ability of logical reasoning, numerical calculation and approximation to the nonlinear function.However, the structure and approximation of the double-input and single-output (DISO) fuzzy system is the key to the further study on multiple input single (multiple) output fuzzy system. In this paper, we will popularize the conventional fuzzy inference machine to a class of regular implication operators, and constructed three kinds of DISO fuzzy systems based on the implication operators, parameter singleton fuzzifier and center of gravity defuzzifier, and then the analytical expressions of the input and output of the fuzzy system are derived.