The invention brings forward a speed control modeling method of a cruise missile. Through combination with a description of dynamic features of a ramjet engine, a composition and modeling flow of a speed control loop is given. The method specifically comprises modeling of the ramjet engine, a speed loop total model for simulation and a small-disturbance model for control. A foundation is laid for performance evaluation of the cruise missile and design of a controller. The speed control loop modeling method for simulation, brought forward by the invention, effectively reflects interface relations among a projectile body, the ramjet engine, atmosphere environment, a measurement apparatus and the controller, and provides a basis for realizing engine performance and total performance evaluation and technical indexes. The small-disturbance model modeling method for control, provided by the invention provides a reasonable design model for the design of a speed controller and can effectively improve the control quality.