The aim of the present study was to evaluate the clinical efficacy between manual buffy coat-derived platelet concentrates (PCs) and automated apheresis platelet concentrates (APCs) in terms of their therapeutic effects. The corrected count increment (CCI) was calculated according to detected differences in platelet concentration in patients who underwent transfusion of APCs, prepared by an automated system (group I, 72 cases) or PCs derived from buffy coat by manual method (group II, 83 cases). The clinical efficacy was assessed in terms of the CCI and clinical symptoms. The platelet contents of all the PCs were detected before transfusion. The mean 1 h CCI was 13.56±4.45 and 24 h CCI was 8.67±4.21 in group I, while the mean 1 h CCI was 15.83±4.65 and 24 h CCI was 9.57±3.36 in group II. The effective rates judged by CCI for groups I and II were 53 and 64%, respectively, and those judged by clinical symptoms were 67 and 60%, respectively. In conclusion, the clinical effectiveness of manual PCs was similar to that for APCs; thus, it could be utilized for clinical use.