We evaluated the diagnostic utility of peripheral blood neutrophil distribution patterns obtained using the CELL-DYN SAPPHIRE hematology analyzer in patients with myelodysplastic syndrome (MDS). Peripheral blood was obtained from 467 individuals including 32 patients with MDS, and the respective neutrophil distribution patterns were observed using two light scatters 7-degree complexity (7D) and 90-degree lobularity (90D). These scattering intensities are shown as median (median neutrophil distribution: MND) and coefficient of variation (neutrophil distribution width: NDW). Generally, MDS patients showed lower 7D MND, higher 7D NDW, lower 90D MND and higher 90D NDW than other comparable groups. Whereas 90D parameters were more diagnostically efficient than 7D ones in patients with MDS. The sensitivity and specificity of 90D MND for MDS patients became 78.1 and 78.9%, respectively (cut-off value = 14,514). 90D NDW was most diagnostically effective with 87.5% sensitivity and 91.0% specificity (cut-off value = 21.2%). Both 90D parameters showed no evident correlation with the degree of either leukocytopenia or peripheral blood dysgranulopoiesis. In conclusion, neutrophil distribution parameters, especially 90D NDW, appear to provide convenient and objective markers for the screening of patients with MDS in routine laboratory hematology.