A simple and feasible method was proposed for realization of Lorenz chaotic circuit, which through variable compression let the signal value match the requirements of the circuit design. For improving the efficiency of experiments, the required components were used as less as possible in the circuit designing. The characteristics of this system were analyzed by MATLAB software simulation, the ax+by=c plane was determined by competitive adventure phenomenon. Finally the circuit diagram was designed in electronic circuit simulation software Multisim.