Chronic neutropenia is a myeloid hematologic disorder with a broad spectrum of etiological factors. Selenium trace element deficiency was recently identified as one. We tested the impact of selenium replacement therapy in a patient with chronic neutropenia. All known etiological factors of neutropenia were ruled out and only selenium deficiency was retained. After administration of selenium in the form of seleno-yeast supplement 50 µg daily for 2 month, notable increase in white blood cell (WBC) count and absolute neutrophil count (ANC) was recorded. The supplementation was discontinued for 2 month and monitoring of WBC and ANC revealed gradual decrease of both WBC count and neutrophils. The latter absolute count returned to the prior baseline before selenium supplementation. This suggested that selenium had a clear effect on correcting the low level of WBC specifically neutrophils back to normal level thus reducing the condition of neutropenia in this particular patient.