In fused deposition modeling, the quality of parts can be effectively improved by optimizing the control of the filling speed. However, the filling speed is intercoupled with layer thickness, nozzle temperature and contour corner angle, so it is difficult to optimize the speed control. Based on the bivariate printing experiments, this paper used multivariate nonlinear regression method to construct an optimized control function of the filling speed by considering multiparameter synergistic coupling effect. Combining error analysis, uniaxial tensile and bending test, the effect of the optimization control of the filling speed was tested. Results show that, under the same conditions of processing parameters, by employing the speed optimization method proposed in this paper, samples’ accuracy error values are less than or closed to the average minimum accuracy error value, and the tensile performance can be enhanced slightly. Finally, the influence of this method on the tensile properties is also verified through fracture microscopic morphology analysis.