Abstract: This paper establishes a nodal method to solve the two coupled equations transformed from the transport equation by SP₃ method.In the nodal method,diffusion equation is discretized into average fluxes in the nodes and partial currents on the nodal boundaries.Nodal response relationship is obtained by expanding the detailed nodal flux into a sum of exponential functions.Numerical results demonstrates that the nodal SP₃ method can treat polygonal meshes in different shapes with good parallel property,and that it can provide a similar accuracy while runs about six times faster than the nodal-S_N（N=4） method DNTR under the same mesh.