Abstract: The nonlinear connections defined by K.Yano and Y.C.Wong et al on the tangent bundle are expanded to a nonlinear connection of fibre bundle, this connection on principal fibre bundle (p.f.b) is called formal connection. The classification of 2-rank tensor on p.f.b is discussed with the help of formal connection,and it is pointed out that if we take[rtg qt] as a metric on p.f.b.,then the relation between the metric and the formal connection is constracted, provided q is nonsingular. Finally, using the frame method we calculus the geodesic equation,which is equivalent to the equation of motion for a particle on the Kaluza's unified theory.