An electromotive force estimation method includes steps of: dividing a time series of an electrocardiographic potential to be estimated in a time series of an electromotive force into unit electrocardiographic potential time series such that time series representing electrocardiographic potentials generated by one pulsation of a myocardium are separated from each other; acquiring, for each unit electrocardiographic potential time series, a depolarization electrocardiographic potential time series that is a set of data belonging to a depolarization period, a refractory electrocardiographic potential time series that is a set of data belonging to a refractory period, and a repolarization electrocardiographic potential time series that is a set of data belonging to a repolarization period; estimating a depolarization electromotive force time series indicating an electromotive force at each time point in the depolarization period based on the depolarization electrocardiographic potential time series; estimating a refractory electromotive force time series indicating an electromotive force at each time point of the refractory period based on the refractory electrocardiographic potential time series and an estimation value of the electromotive force at an end time point of the depolarization period; and estimating a repolarization electromotive force time series indicating an electromotive force at each time point of the repolarization period based on the repolarization electrocardiographic potential time series and an estimation value of the electromotive force at an end time point of the refractory period.