The general expression of the statistical distribution function of photons in two-photon Jaynes-Cummings model (JCM) is derived. The expression can be applied to the cases of any initial light field and any initial atomic state. Under exact two-photon resonance, the features of evolution for the statistical distribution of photons in JCM with the initial coherent state field and the initial squeeze state field are studied in detail. These two cases show striking difference.