Abstract: An ON/OFF detection device is configured to detect ON/OFF of an input unit using a load sensor, and includes a threshold setting unit, a comparison unit, and an ON/OFF determination unit. The threshold setting unit is configured to set a threshold value with respect to a previous detection value of the load sensor. The comparison unit is configured to compare the threshold value and a current detection value. The ON/OFF determination unit is configured to determine ON/OFF of the input unit based on a comparison result. When a previous determination result of the ON/OFF determination unit is ON, the threshold setting unit is configured to set the threshold value to be lower than the previous detection value. When the previous determination result of the ON/OFF determination unit is OFF, the threshold setting unit is configured to set the threshold value to be higher than the previous detection value.