A nonvolatile recording method with double modulated UV beams in (Ce,Cu)∶LiNbO3 crystals is proposed. Compared with the normal UV-sensitized nonvolatile holographic system, the amplitude of the refractive-index changes is greatly increased and the recording sensitivity is largely enhanced by recording with UV light in the (Ce,Cu)∶LiNbO3 crystals. Temporal evolutions of the photorefractive grating and the diffraction efficiency are effectively described and numerically analyzed based on jointly solving the two-center material equations and the coupled-wave equations. Roles of doping levels and recording-beam intensity in the process are discussed in detail. Investigations show that gratings recorded in the deep and shallow centers are in phase, the value of the total grating (the superimposition of the deep and shallow gratings) is the summation of those of the two gratings; in the fixing phase, the depth of grating in the deep center is enhanced; the amplitude of the refractive-index changes increases with increasing the concentrations of the deep and shallow centers, and larger recording intensity results in the stronger total grating and the larger value of the recording sensitivity. Theoretical results can confirm and predict experimental results.