Drilling force variation rules at drilling process for improving the design of tool and measuring bone injury are important. The regression orthogonal experiment and multiple linear regression method were used to manager experiment data and the prediction model of drilling forces was established. It is indicated that the diameter has the greatest influence on the drilling force, the feed rate is the second, the drilling speed is the last. By choosing correct drilling parameters, the processing efficiency can be improved by controlling the cutting parameters, the optimal drilling force can be obtained.