The invention discloses an optimized mice somatic cell nuclear transplantation method. According to the mice somatic cell nuclear transplantation method, three kinds of cells, including cumulus cell, fetal fibroblasts, and embryonic stem cell, are adopted to construct reconstructed embryos; the activation efficiencies of three reconstructed embryos in different activation mediums are compared, development efficiencies in different solutions are compared, and pregnancy efficiencies of different embryo transplantation methods are compared; it is concluded that calcium-free KSOM activation medium is a universal high efficiency activation medium, and the activation efficiency is about 93.5%; KSOM-AA culture medium is suitable for in vitro culture of the reconstructed embryos of cumulus cells and embryonic stem cells, and the best culture medium for fetal fibroblasts is alpha MEM culture medium; when the reconstructed embryos are at 2-cell period, nuclear transplanted animals can be obtained via transplantation of embryos through bilateral fallopian tubes, wherein for each fallopian tube, transplantation of 15 embryos is carried out. The optimized mice somatic cell nuclear transplantation method is capable of increasing reconstructed embryo cleavage rate, blastula development rate, cloning animal birth rate, and survival rate, so that the success rate of obtaining embryonic stem cells from the reconstructed embryos is increased.