In the rotatingwave approximation,the evolution of the field quantum entropy in the system that consists of a twolevel atom interacting with a singlemode field was studied,considering the atomic motion and the field frequency varying with the time in the form of sinefunction at the same time.In two cases of neglecting atomic motion and considering atomic motion,figures of the time evolutions of the field entropy were plotted respectively using numerical calculations.Influences of the atomic motion,the fieldmodel structure parameter,amplitude and angular frequency of the fieldfrequency variation on the field entropy were also discussed.The atomfield entangled states,field fock states and atomic high fidelity states were prepared by analytic method according to the decomposition theorem of Schmidt,and the related system parameters of these quantum states operation were acquired.The results show that:the time evolution behavior of the field entropy is modulated by the frequency variation of field; the interaction between the field and atom will weaken with the increase of the amplitude of variation of the field frequency; the period of the field entropy agrees with the period of fieldfrequency variation; the atomic motion will result in the period of the field entropy doubled; the evolution of the field entropy is related to the parity of fieldmode structure parameter; the approximate EPR states of fieldatom can be prepared periodically whether the atom moves or not.