Abstract: The study on porcine somatic nuclear transfer is of the great meaning in the field of biomedicine. This experiment was conducted to study enucleated method, which is one of the key techniques for animal cloning. The results show that the modified Willadsen’s method for enucleation, called two-step-squeezing method, is significantly better than McGrath-Solter’s method in the enucleated rates （73.9%, 42.5%,P＜0.05） and the rates （81.2%, 67.4%, P＜0.05） of absolutely removing nuclei matter. It was also found that the rates （89.1%） of absolutely removing nuclei matter for 36h-matured-in-vintro oocytes is significantly higher than that for 44h group （55.8%, P＜0.05）.

Key words: Pig, Oocytes, Enucleation, Nuclear transfer