Although reports of typical acute promyelocytic leukemia (APL) cases rarely mention dysplastic changes, this report concerns a rare case of APL with tri-lineage dysplastic changes resembling the characteristic features of myelodysplastic syndrome (MDS). The patient, a 77-year-old Japanese male, was diagnosed as having pancytopenia with hematologic morphological abnormalities comprising micro - megakaryocytes, neutrophils with hypo-granulation and negative peroxidase activity, and erythroblasts containing nuclei with abnormalities such as karyorrhexis. Although there is one report of a case of transformation of de novo MDS into APL and several reports of cases of therapy-related MDS transformed into APL, our patient had no history of cytopenia or of either chemo or radiation therapy. Our case can thus be considered to constitute a rare case of APL with dysplastic morphology.