To estimate the condition of an object precisely, even while the object performs a turning motion, an estimation device for calculating a predicted position of an object existing on the periphery of a host vehicle includes: position calculating circuit for detecting a position of the object; Doppler velocity calculating circuit for calculating a Doppler velocity of the object; host vehicle velocity obtaining circuit for obtaining a host vehicle velocity; host vehicle turning radius obtaining circuit for obtaining a turning radius of the host vehicle; and predicted position calculating circuit for calculating the predicted position of the object on the basis of the position of the object, the Doppler velocity, the host vehicle velocity, and the turning radius of the host vehicle.