Milling force is large during disc milling grooving of titanium alloy because of big diameter of the cutter and large cutting output， which leads to obvious vibration of cutter and shorter tool life. In the study， in order to optimize and control the process of disc milling grooving in titanium alloy， single factor experiment and orthogonal experiment are designed， and milling force is measured by three-way piezoelectric dynamometer. The prediction model of milling force is built by linear regression method， and the significance of model is checked by “F” test method. The effect of technological parameters on milling force is analyzed by the extremum difference analysis. The interaction effect of technological parameters on milling force is studied by response surface method. Experiment results show that the sensitivity to changes in cutting depth is in the order of milling force F_x >feed speed>spindle speed. The sensitivity to feed rate changes is in the order of milling force F_y >cutting depth>spindle speed. The sensitivity to milling force F_z changes in the order of spindle speed>cutting depth. Milling force decreases with the increase of spindle speed and increases with the increase of cutting depth and feed speed. In addition， milling force F_x is greater than F_y and F_z， which plays a leading role in machining performance and tool wear.