CONTACT DETECTION DEVICE

A contact detection device includes an electrostatic capacitance sensor provided on a steering wheel of a vehicle, and configured to detect contact of a human body with the steering wheel, an estimation unit configured to estimate whether the human body is in contact with the steering wheel, and a diagnosis unit configured to conduct a failure diagnosis related to the electrostatic capacitance sensor, based on a detection result of the electrostatic capacitance sensor in a case where the estimation unit estimates that the human body is in contact with the steering wheel and a detection result of the electrostatic capacitance sensor in a case where the estimation unit estimates that the human body is in no contact with the steering wheel.