This paper aims to reduce the milling force and milling heat in order to reduce the deformation of the 7075-T651 aluminum alloy workpiece and improve the metal removal rate. In this paper, a method for simultaneous optimization of two kinds of parameters (milling parameters and tool geometric parameters:rotation speed, feed rate, radial depth of cut, axial depth of cut, rake angle and clearance angle) was proposed, which could achieve multiple objectives (milling force, tool milling temperature and metal removal rate). Based on the partial least squares regression model and the finite element simulation results of milling 7075-T651 aluminum alloy workpiece, the functional relationship model between milling force and tool milling temperature and metal removal rate of two types of parameters were established, and 8 typical multi-objective optimization algorithms were used to solve the above models. By visualizing the Pareto front surface and HV performance index, the optimal solution algorithm that can solve the problems in this paper was screened. The optimal solution values of milling parameters and tool geometric parameters were obtained, such as rotational speed 5 966.30 r/min, feed 0.08 mm/z, radial cutting depth 4.53 mm, axial cutting depth 4.99 mm and rake angle 17.95°, clearance angle 2.00° for tool geometric parameters. At this time, the corresponding milling force is 232.12 N, tool milling temperature 3 is 22.56 ℃, and the metal removal rate is 33.08 mm3/min). The optimization results can achieve comprehensive control objectives such as lower milling force and milling temperature and higher metal removal rate, and have practical application value in reducing workpiece deformation and improving machining efficiency during milling of 7075-T651 aluminum alloy workpiece.