The invention provides a method for optimizing speed and controlling smooth movement in a high-speed machining center, which relates to the technical field of high-speed machining. The high-speed machining center requires that the feeding speed reaches 40m/min, the acceleration reaches 2g and a machine tool can smoothly run during machining a minuscular section. The method consists of the two steps of feeding speed optimization and pre-acceleration and pre-deceleration control. The speed optimization considers the corner factor of a machined section and the restriction of the machine tool speed and the acceleration, a simplified integral optimization model is obtained through relevant analysis so as to ensure the real-time of computation, and an analysis computing formula for the simplified model to optimize each decision variable step by step is given according to the primary and secondary analysis of the influence degree of the decision variable to a target function. The method for optimizing speed and controlling smooth movement can ensure that the feeding speed of the high-speed machining center is smoothly linked without changing the control software structure of the original numerical control system.