An object detection device includes: a transmitter transmitting a transmission wave; a receiver receiving a reception wave reflected by an object; a CFAR processor acquiring a CFAR signal at a detection timing by CFAR processing based on a value of a first processing target signal and an average value of values of second processing target signals; a detection processor detecting information related to the object based on a comparison between the CFAR signal and a threshold; and a threshold processor setting, when the detection timing belongs to a predetermined first section, the threshold as a first threshold calculated in consideration of a detection result of a temperature sensor, and setting, when the detection timing belongs to a predetermined second section, the threshold as a second threshold calculated without considering the detection result of the temperature sensor.