The radar signal processing device includes: a transmitter; a receiver configured to acquire a received signal based on a reflected wave received from the object; a detector unit configured to detect information to be used for type determination of the object from the received signal; an object determination unit configured to determine a type of the object; and a control unit configured to identify a weighting factor set for each piece of the information to be used for the type determination of the object based on a characteristic of the received signal. The object determination unit is configured to obtain a total sum value by multiplying the corresponding weighting factor identified by the control unit for each piece of the information detected by the detector unit, and to determine the type of the object based on the total sum value.