Abstract: Near-field electric field and dipole moment are divided into two parts respectively,transverse part and longitudinal part,and the interaction energy of transverse part and longitudinal part is obtained.Moreover,we get the interaction force of transverse part,longitudinal part and the total part.Numerical results show that dipole-dipole interaction energy and force decrease sharply with the distance of dipole-dipole,and change periodically along with the angle between dipole moment and axis of the system changing.