Experimental cryosurgery on 9 cases of the dogs and one human clinical case were described. Results obtained showed the enough possiblity of the method for the surgery of the malignant tumors. By the method the surgical operation will be performed characteristically with lesser influences in the following aspects, i.e., in bleeding, pain the inframatroy reaction and the malignant metastasis during anf after the invation and it will be carried out with only easy control in even the poor risk cases.