A threedimensional differential system derived from the Chen system was analyzed, whose basic dynamical behaviors and the existence of attractor based on the first Lyapunov coefficient were discussed. The stability of the equilibrium point of this system was studied using the nonlinear system theory and RouthHurwitz theorem, and the corresponding theorems were obtained. At the same time, the linearization of the system made the coefficient matrix of this system have a pair of purely imaginary conjugate roots and one negative real root, and bring a Hopf bifurcation on the equilibrium point. Then, the Lyapunov method and the highdimensional Hopf bifurcation theory were applied to investigate the local bifurcation. And the bifurcation and stability were analyzed by the 2dimensional local center manifold theorem, and some subcritical and supercritical conditions were obtained. Finally, the discussion was verified by numerical simulation.