Using finite element method, the varying rule of mechanical parameters with technology parameters was analyzed systematically in multi-wedge cross wedge rolling forming automobile semi-axes. The testing system of mechanical parameters by using computer-collected data was developed. Through this testing system, the influence rule of rolling force and rolling moment at different technology parameters was tested on line. The result of test corresponded with the theoretical analysis. The research results provided important theory foundation for defining parameters of rolling force and rolling moment for developing multi-wedge cross wedge rolling mill of forming automobile semi-axes.