Objective To evaluate the clinical significance of detecting platelet parameters in platelet transfusion patients by Investigating the relationship between platelet parameters and efficacy of platelet transfusion and prognosis.Methods A total of 50 patients who underwent platelet transfusion in our hospital in 2014 to 2016 were reviewed.Patients divided into two groups (with normal platelet counts group or subnormal platelet counts group) according to outcomes of blood biochemistry and routine after five days of platelets transfusion.Platelet parameters (platelet count,platelet distribution width,mean platelet volume,large platelet ratio) and CCI were evaluated by statistical analysis.Results The numbers of patients with CCI＞4.5 in normal platelet counts group is 21 (77.78％),that in subnormal platelet counts group is 11 (47.83％).Platelet parameters before transfusion showed no significant difference between two groups (P＞ 0.05).After transfusion,in normal platelet counts group Plt,PDW,MPV and P-LCR were significantly higher than another group (P＜0.01).MPV and P-LCR were increased in normal platelet counts group,and decreased in normal platelet counts group after transfusion.Condusion Detection of platelet parameters,especially MPV and P-LCR,is important for evaluating the efficacy and prognosis of platelet transfusion.