Objective To explore a simplified method of coagulation test for the individuals with erythrocytosis. Methods The antico-agulants, blood volume and fixed blood collecting volume were adjusted by the formula: anticoagulants (mL)＝(100－HCT×100)× blood (mL)×0.001 85. A total of 124 blood samples for coagulation testing in which the calcium ( Ca2+) interval was designated and hematocrit (HCT) was more than 55% were tested with calibrated anticoagulants, adjusted blood volume and fixed blood collection vol-ume [anticoagulant(mL)/0.055 5]. The results of plasma prothrombin time (PT), international standardization ratio (INR) and acti-vated partial thromboplastin time (APTT) before and after adjustment were compared. The results of the samples from 3 groups after adjustment were also compared. The relationship of HCT with unadjusted PT and APTT were simultaneously observed. Results The unadjusted results of PT, INR and APTT were significantly higher than those after anticoagulants adjustment (27.52±16.37 vs 12.49± 1.35, 2.31±1.47 vs 0.99±0.11 and 50.09±13.32 vs 33.37±5.05) with statistically significant difference in paired comparison (P＜0.05). No statistical difference was found in the comparison of the results for PT, INR and APTT after adjustment within the 3 groups ( PT: 12.49±1.35 vs 12.84±1.54 vs 12.82±1.76, INR:0.99±0.11 vs 1.02±0.13 vs 1.02±0.15, APTT: 33.37±5.05 vs 33.49±5.09 vs 32.83±5.06) (P＞0.05). HCT values of the patients were positively correlated with unadjusted PT (r＝0.461, P＜0.05) and APTT (r＝0.571, P＜0.05). Conclusion The coagulation test of the individuals with erythrocytosis may use to adjust the blood volume and the fixed blood collection volume provided calcium concentration in reference interval.