The purpose of this study was to investigate the incidence of clinically common EDTA-dependent pseudo-thrombocytopenia (EDTA-PTCP) and methols for treating this diseese. A total of 1326 cases of thrombocytopenia found at blood routine examination were amalyzed anong 71 535 patients hospitalized in our hospital from January 2010 to May 2013, and 87 cases of PTCP caused EDTA-K anticoagulant were analyzed again by using sodium citrate auticoagulant, at the same time the platelet formation distribution was observed by microscopy of smear with Wright-Giemsa staining. The results showed that the platelet count detected by using EDTA-K anticoagulant in 87 cases was (56 ± 27)×10(9)/L, while the platelet count detected by using sodium citrate was (185 ± 39)×10(9)/L (t = 1.83,P < 0.01). The pseudo-thrombocytopenia incidence cansed by EDTA-K was 0.12%, it was 6.56% for the total number of thrombocytopenia. It is concluded that the incidence of PTCP cansed by EDTA-K is 0.12%, the PTCP is easily misdiagnosed. Therefore, the specimens of platelet count <100 10(9)/L should be tested again. When the platelet aggregation is found, the specimens should be examined again by using sodium citrate in order to avoid misdiagnosis.