In order to study the optical effects of turbulent intermittency,a simplified non-Gaussian random field model has been constructed,which can model atmospheric dielectric permittivity(or refractive-index) fluctuation approximately.Four arbitrary functions enter into the characteristic functional of this model.Using the properties of the atmospheric turbulence,such as the statistical homogeneity,the single-point probability distribution and the spectrum of the refractive-index fluctuations,these functions can be selected or determined.With these given functions,we have studied the statistical properties,especially the mean field adn the mutual coherence function,of a plane partially coherent incident wave.A simple example of numerical simulation has also been presented.