〔Abstract〕 Objective To detect the expression of autoantibodies in patients with immune thrombocytopenia(ITP) by flow cytometric immuno-bead array, as well as explore its clinical significance in the diagnosis of ITP patients, and the relationship between the types of platelet specific autoantibodies and the clinical effects of drugs. Methods Flow cytometry immuno-bead array was used to detect the expression of anti platelet membrane glycoprotein Ⅰb(GPⅠb) antibody and antiplatelet membrane glycoprotein Ⅱb/Ⅲa(GPⅡb/Ⅲa) antibody. The results of 71 cases were compared with those of monoclonal antibody capture specific platelet antigen(MAIPA). Patients with ITP were halved into the groups of hormone treatment and recombinant human thrombopoietin( rh TPO) treatment,with49 and 28 cases respectively,and 4 cases from the other groups. Moreover,the patients were divided into effective group and ineffective group based on the clinical effects. Results(1) Results of flow cytometric immuno-bead array: There were comparatively 30 and 29 patients with positive anti GPⅠb antibody and anti GPⅡb/Ⅲa antibody,making the positive rates 42. 25% and 40. 85%. Upon the combined detection of the two antibodies,42 patients were finally positive,with a total positive rate of 59. 15%.(2) Results of MAIPA method: there were 19 and 22 cases of patients with the two antibodies,and the positive rates were 26. 76% and 30. 99% respectively. The combined detection of the two antibodies was 33 cases creating a total positive rate of 46. 48%.(3) The comparison between the above two methods showed no significant difference( P>0. 05).(4) The results of the 49 patients in hormone therapy whose antibody expression was detected by flow cytometry showed that there were 19 and 30 cases with positive anti GPⅠb and with negative anti GPⅠb with the effective rates 42. 11% and 73. 33%. The difference was statistically significant( P<0. 05). Conclusion Compared with MAIPA method,flow cytometric immuno-bead array is more speedy in detecting the platelet-specific autoantibody,but the sensitivity is not different. It is of great significance for the clinical diagnosis of ITP patients. In addition,the reason why the effect of glucocorticoid treatment is not obvious may be related to the positive anti GPIB antibody.