In order to characterize the dielectric properties of compositesd of inorganic nanocrystals and polymer,their entire poling mechanisms were considered.For inorganic nanocrystals and polymer,the relaxation theories of Debye and NH function were used,respectively.Through using Onsager effective field theory,the plural dielectric constant of this kind of composite was calculated.Nanocomposite thin films PT/PEK C were prepared.It was founded that the calculation values of the real dielectric constants of the films were coincided with the experiment values of that.