An energy storage device state estimation device for estimating a state of an energy storage device at a predetermined point of time, the energy storage device state estimation device comprising: a history acquisition part configured to acquire a charge-discharge history of the energy storage device up to the predetermined point of time; a deterioration value estimation part configured to, assuming information indicative of a deterioration degree of time dependent deterioration in which the energy storage device deteriorates with a lapse of time in an open-circuit state as information about time dependent deterioration, assuming information indicative of a deterioration degree of working electricity dependent deterioration which is deterioration by working electricity excluding the time dependent deterioration as information about working electricity dependent deterioration, assuming a value indicative of an amount of the time dependent deterioration of the energy storage device as a time dependent deterioration value, and assuming a value indicative of an amount of the working electricity dependent deterioration of the energy storage device as a working electricity dependent deterioration value, estimate the time dependent deterioration value and the working electricity dependent deterioration value at the predetermined point of time respectively using the information about time dependent deterioration and the information about working electricity dependent deterioration respectively corresponding to the charge-discharge history; and a state estimation part configured to estimate a state of the energy storage device at the predetermined point of time using both the time dependent deterioration value and the working electricity dependent deterioration value. a history acquisition part configured to acquire a charge-discharge history of the energy storage device up to the predetermined point of time; a deterioration value estimation part configured to, assuming information indicative of a deterioration degree of time dependent deterioration in which the energy storage device deteriorates with a lapse of time in an open-circuit state as information about time dependent deterioration, assuming information indicative of a deterioration degree of working electricity dependent deterioration which is deterioration by working electricity excluding the time dependent deterioration as information about working electricity dependent deterioration, assuming a value indicative of an amount of the time dependent deterioration of the energy storage device as a time dependent deterioration value, and assuming a value indicative of an amount of the working electricity dependent deterioration of the energy storage device as a working electricity dependent deterioration value, estimate the time dependent deterioration value and the working electricity dependent deterioration value at the predetermined point of time respectively using the information about time dependent deterioration and the information about working electricity dependent deterioration respectively corresponding to the charge-discharge history; and a state estimation part configured to estimate a state of the energy storage device at the predetermined point of time using both the time dependent deterioration value and the working electricity dependent deterioration value.