We present a method for automatic synthesis of CMOS op-amp circuit and a data array description method of analog circuit.This new technique of circuit synthesis overcomes the limits of selection-based circuit design technique which relies on the designer's experience and the limits of construction-based circuit design technique which is difficult to take advantage of the successful experience of circuit design.With the prerequisite of no invalid circuit structure,this new technique,starting from classic sub-circuit model,automatically creating op-amp circuit,guarantees the quality of circuit construction.The data array description method of analog circuit,based on successful design experience,is able to solve the circuit connection problem of multiple terminal devices effectively.Results are reported to validate the effectiveness of this approach for topology-design automation of CMOS op-amp circuit.