The present invention provides a blood analysis method, a blood analysis device, and a storage medium containing an executable program, with which it is possible to ascertain the effect of platelets on measurement results. The blood analysis method comprises the steps: acquiring optical information which changes over time from a mixed liquid of a blood sample and a reagent for coagulation time measurement after mixing the blood sample and the reagent and acquiring information related to a coagulation time and information related to a number of platelets in the blood sample based on the acquired optical information.