A high proportion of new energy is connected to the power system through converters, which reduces the frequency support ability of the power system and affects the synchronization stability of the system. Small signal modeling and stability analysis are presented for a hybrid power system composed of a grid-forming (GFM) converter, a grid-following (GFL) converter, and a synchronous generator. Firstly, small signal modeling is conducted on a hybrid power system composed of a GFM converter controlled by a virtual synchronous generator, a GFL converter based on a phase lock loop (PLL), a synchronous generator, and other components. To verify the correctness of the signal model, the established small signal model is compared with the actual circuit model for the same step power disturbance. Secondly, the eigenvalue analysis method is used to analyze the influence of changes in the penetration rate of new energy and GFM converter on the small signal stability of the system, and the participation factor method is employed to analyze the degree of influence of relevant state variables on the system eigenvalues. Then, the influence of the virtual moment of inertia and virtual impedance in the control parameters of the GFM converter on the small signal stability of the system is analyzed. Finally, the accuracy of the theoretical analysis is verified through simulation.