In the present paper, the Nottingham's Empirical Formula of the transmission coefficient is used to develop the DuBridge's theory of initial energy distribution of photoelectrons from metal. Owing to the detailed considerations of refraction effect for an electron passing through the potential barry of the surface, we discuss not only the energy distribution and the normal energy distribution of photoelectrons, but also the angular distribution. All discussions are based on the following assumptions:(1) The surface is ideal;(2) The energy distribution of electrons in the metal is according to the Fermi-Dirac distribution;(3) The intensity of incident monochromatic light is constant and the incident light is unpolarized.The obtained formula of initial energy distribution of photoelectrons is very simple, but it is more satisfactory than the other theories shown in this paper. The curve of angular distribution of photoelectrons is like an egg with its large end outward. If there is no refraction effect, the angular distribution satisfies Lambert's law. The spectral distribution, the theoretical formula of volt-ampere characteristic under the retarding field of a spherical condenser with a small photocathode as one electrode at centre, the normal energy distribution, and the theoretical volt-ampere characteristic of ideal parallel plate condenser are also discussed in this paper.