In order to determine the force and energy parameters of cold roll-beating of external spline, the characteristics of deformation zone in cold roll-beating are analyzed. The parameters and position of the deformation zone change with the movement of the Roller, the contact arc and the reduction are very small, and there is an incomplete deformation zone in the initial stage of cold roll-beating. An analytical method for calculating the unit pressure and deformation force is proposed. A cold roll-beating process is discretized into an infinite number of cold rolling processes with complex sections. The analytical formulas of unit pressure and deformation force in cold rolling are given, and the unit pressure value and its distribution characteristics are determined. In order to verify the analytical method, the finite element model of cold roll-beating is established and the forming force of cold roll-beating is calculated. The horizontal milling machine is modified to carry out the cold roll-beating experiment, and the cold roll-beating forming force was measured. The predicted results of the analytical formula are compared with the simulation and measured results. The results show that the maximum error of radial force is about 7% and 4% respectively, and the variation curve of radial force is basically consistent, but the time of one cold roll-beating process is slightly shorter. The analytical method correctly predicts the magnitude and change process of cold roll-beating forming force.