The classical Maxwell equation set, in combination with the quantum theory, is applied to establish an electromagnetic biologic non-thermal model, i.e. to define the relation between energy of photons coming into biological cells and applied weak electric field intensity. A broadband transverse electromagnetic (TEM) transmission cell is used to investigate the electromagnetic (EM) biologic non-thermal effect of applied weak electric field (WEF) intensity on incubation of empoasca vitis gothe eggs. The result has demonstrated that there is a threshold necessary for the applied electric field intensity during non-thermal effect on incubation of empoasca vitis gothe eggs; a positive effect occurs at the intensity below the threshold and a negative one takes place at the intensity above the threshold. So the model has proved correct and effective.