The emission cross sections and excitation cross sections have been measured in collisions between N4+ ion and Na atoms. The experimental results show that the excitation cross sections of NaI(3p-3s) are vety large, about １０-15ｃｍ2 . The data of cross sections have been given in this paper and reasons for the large excitation cross sections of NaI(3p-3s) have been discussed qualitatively.