By applying the material removal model of polishing with a flexible pad，a parameter control method of curved surface polishing with trochiod trajectory is proposed． First the contact state of a flexible pad and work-piece surface is determined． Pressure prediction model is then established by using the support vector machine method and the pressure distribution of contact area is founded． Then the material removal model is set up by using Preston equation． According to the relationship between radius and step，the trochoid trajectory can be divided into two cases: single-cycle with two overlapping regions and single-cycle with three overlapping regions． Based on the removal model，one single trochoid path is divided into two parts to overlap respectively and then the total overlapping is established according to the width of the overlapping region，so as to control the trochoid trajectory parameters to achieve the optimal removal overlapping． The results of removal rate simulation and robot polishing experiment show that the work-piece surface roughness reaches 0. 57μm after polishing，which indicates that the proposed parameter control method of trochiod trajectory is feasible for high precision curved surface polishing．