Abstract: Objective: to establish a reference value of the reticulocytes counts and its subpopulation in the elderly, and study the value of its clinical applications in anemias diagnosis and leukemias chemotherapy. Methods: The reticulocytes were measured by automated hematology analyzer （ADVIA 120） with oxazine 750 as fluorochrome in 338 the healthy elderly and 141 aged hematological disorders. Results: The Student′s t-test showed that there were no significant differences（P＞0.05）between male and female in the healthy elderly for reticulocyte percentage （RET）, reticulocyte absolute number（RET#）, High fluorescence reticulocyt（HFR）,middle fluorescence reticulocytes（MFR） and low fluorescence reticulocytes （LFR）. They were 0.0140± 0.0045,（62.22±19.28）×10⁹/L、0.8571±0.0441、0.1190±0.0336 and 0.0239±0.0139。There were significant differences（P＜0.05）between anemias and reference value in the elderly for RET# and HFR+MFR. RET# and HFR+MFR was extremely decreased in leukemias after chemotherapy. HFR+MFR rise faster than RET# and the absolute neutrophil count （ANC）in bone marrow recovery. Conclusions: Reference value of the reticulocyte counts and its subpopulation were not correlated with sex in the healthy elderly. RET# and HFR+MFR have important significance in classification and difference diagnosis of anemias, estimation of bone marrow recovery after chemotherapy in the elderly.