Pooled platelet concentrate (PC) that is prepared from whole blood may be a solution to the shortage of blood donors caused by the declining birthrate and aging population. Here, we prepared a pooled platelet additive solution (PAS)-PC from 400 ml whole blood by replacing a portion of the plasma with PAS using TACSI, a Europeanspecification large-capacity centrifuge with an automatic blood separation function. We then compared quality during storage at room temperature (22℃) and refrigeration (4℃) over 21 days.Pooling of four buffy coats (BCs) yielded more than 10 units of pooled PAS-PC (n=4), and pooling of five BCs yielded more than 15 units of pooled PAS-PC (n=4). Each pooled PAS-PC met the quality standard of PC in Japan. On room temperature storage, pooled PAS-PC maintained good platelet aggregation, % hypotonic shock response (%HSR), and clot formation capacity for up to 5 days. On refrigerated storage, %HSR decreased early after storage, but aggregation and clot formation capacity remained similar to those on day 5 of room temperature storage until day 14.These findings suggest that pooled PAS-PC of good quality can be obtained from 400 ml whole blood using the European specification TACSI. In addition, pooled PAS-PC can be stored for up to 14 days by refrigerated storage.