With the advent of the era of rapid information growth, the demand for data bandwidth continues to increase. Vertical-Cavity Surface-Emitting Lasers (VCSEL) have been widely used as a new type of optical communication devices. Starting from the parasitic circuit of the semiconductor laser, the internal photoelectric conversion process of the VCSEL is analyzed, and the parasitic characteristics of the intrinsic laser and the external package are considered. The large-signal and small-signal equivalent circuit models are built respectively, and the simulation is carried out using Python language and Pspice software. The influences of spontaneous emission coefficient and optical confinement factor on the threshold current are analyzed in the large-signal model, and the influence of parasitic network parameters on the modulation response bandwidth is discussed in the small-signal model. The simulation results show that the threshold current of the VCSEL device can be reduced, and the modulation bandwidth can be increased, by adjusting the spontaneous emission coefficient, optical confinement factor and parasitic network parameters.