This article establishes a model for machining orientation control of a five axis CNC machine tool based on methods such as constructing translation matrix, rotation matrix, and composite matrix. Using the optimal path and rotation angle search algorithm based on rotation transformation and composite transformation, the displacement of the machining center relative to the initial state, the rotation angle of the rotation axis, and the drilling number under the minimum total displacement and total rotation angle are studied. For the given machining task and initial state, since the required holes (simplified as line segments) are all perpendicular to the X-axis, Bi=0 is obtained. This article first obtains the rotation angle Ai around the A-axis through the given angle conditions, and then establishes a composite transformation equation around the A-axis to solve for the new coordinates of each machining center, hole and plate intersection point after composite transformation. The displacement from the intersection point to the drill bit is the same as the displacement from the machining center to the drill bit, in order to determine the displacement of the machining center relative to the initial state. If the parameters of the first hole processed are (x1, y1, z1), , the displacement of the machining center relative to the initial state, and the required rotation angles . (A1, B1, X1, Y1, Z1)=(66, 0, −15, −159.732, 113.082) 1..