A spinning missile with control system was chosen as the research object in this paper. The dynamic model of the spinning missile was improved in theory by considering nonlinear aerodynamics and time delay in control segment. Setting time delay and control gains as the bifurcation parameters, stability analysis of one equilibrium point was made based on the characteristic equation of this model. Critical Hopf bifurcation values were obtained when the equilibrium point lost its stability. Then, the instable states of the attack angle and sideslip angle were numerically simulated under theoretical prediction. Meanwhile, the amplitude of periodic solutions changing with congtrol gains and tiem delay were achieved. The numerical results indicate that the theoretical prediction is relatively reasonable. Time delay made little change on the coning motion of the spinning missile, but it dramatically decreases the selectable ranges of control gains in keeping the system stable. In consequence, time delay can not be ignored for designing stability system of the spinning missile.