An estimation device includes: M transmission antenna elements each transmitting a first transmission signal; N transmitter-receivers each including a reception antenna element and receiving, over a predetermined period, a first reception signal including a reflection signal that is the first transmission signal reflected by a first living body, using the reception antenna element; a memory storing training signals that are second reception signals obtained by causing the N transmitter-receivers to preliminarily receive second reception signals including reflection signals that are second transmission signals transmitted from the M transmission antenna elements to a second living body and reflected therefrom; a first vector calculator calculating a first vector for each training signal and each first reception signal by respective predetermined methods; and a circuit identifying the first living body or estimating an orientation of the first living body by a predetermined method, using correlation coefficients calculated from the first vectors.