We use a second order perturbation expansion of the evolution operator T to deduce the efficiency Hamiltonian form of two nonidentical atoms in a highly-detuned optics cavity with single mode;the two nonidentical atoms state vector with time evolution is studied under the initial state in a two-atom direct product in a vacuum optical cavity. The result shows as follow： （1） the two-atom state vector keep a direct state form and do not produce any entangled state under the condition ｜△1-△2｜ 〉〉 max（g1,g2） or △1＋△2=0,（2） the two-atom state vectors evolve into the entangled state from the initial state in a direct state, and realize a maximal entangled state at a given time under the condition ｜△1-△2｜〈〈max（g1,g2）.