A parallel five-microring resonator model is proposed. The output function of parallel microring is modeled by transmission matrix method, and Matlab simulation software is used to analyze the output spectrum intensity. The spectral output characteristics of resonator bands and superposition bands are researched when ratio between microring spacing and microring circumference are 0.25 and 0.50, respectively. By optimizing the coupling coefficient of transmission, system refractive index, microring radius and other parameters, the resonator frequency bands whose shape factor is larger than 0.85 and stopband crosstalk is less than -25 dB are obtained. Four parallel microring arrays are cascaded to achieve 1×4 dense wavelength division multiplexer.