Two cases of myelodysplastic syndrome (MDS) and a case of acute nonlymphoblastic leukemia (ANLL) with a trisomy 14 are presented. The series of results derived from our cases, and those previously reported, strongly suggest that this anomaly may be another nonrandom change, confined within myeloid disorders and associated with patients' advanced age, marked tendency to bone marrow dysplastic features, normal platelet values, and not unfavorable prognosis.