To evaluate present status of surgical transfusion during operations in our operating room, we analyzed the amount of preoperative preparation of blood for an operation, and frequencies for transfusion in cases of various departments and kinds of operation using cross-match to transfusion ratio (C/T ratio). Also we evaluated the possibility to establish the national standard guideline of maximum surgical blood order schedule (MSBOS), and compared our trial of MSBOS with other MSBOSs reported based on both local and national levels.Analysis with C/T ratio was very useful to recognize the present status of preparations of blood for surgery preoperatively. We noticed too many preparations of blood preoperatively in our operating room. We tried a trial of MSBOS based on our statistical data in our operating room. When we applied these data to 32 operations, which were analyzed in this study, we could save 80% of blood preoperatively compared with the present preparations of blood for those operations.We considered that realistic C/T ratio is 2, 5, and it is better than 1.5 which is recommended by The Welfare Mimistry in Japan.Guidelines of MSBOS in our hospital were similar to those of other institution reported at both local and national levels. Also we were not able to find differences between our MSBOS and reported those in Japan. We thought that national standard guidelines of MSBOS were valuable to apply to operations by various surgeons and in various hospitals. We therefore recommend that the Japan Society of Blood Tanasfusion make the national guidelines of MSBOS based on national-wide data.