The authors report a case of subacute myelocytic leukemia presenting some severe aspects. The cytogenetic findings show the Philadelphia chromosome ; t (9-22) and a second translocation between the chromosome 12, and the other chromosome 9 : t (9-12). They think that this second translocation represents a supplementary cytogenetic argument for the isolation of "Subacute myeloid Leukemia with Philadelphia chromosome" within chronic myeloid Leukemia.