A capacitive occupant detecting apparatus includes a voltage applying portion, a capacitance sensor, a capacitor, a storing portion, a measuring portion, and a calculating portion. The voltage applying portion applies an alternating-current voltage signal to the capacitance sensor and the capacitor. The storing portion stores a reference voltage. The measuring portion detects a first voltage in accordance with an electric current that flows between the voltage applying portion and the capacitor when the alternating-current voltage signal is applied to the capacitor. The measuring portion detects a second voltage in accordance with an electric current output from the capacitance sensor when the alternating-current voltage is applied to the capacitance sensor. The calculating portion detects an abnormality of the voltage applying portion based on the first voltage and the reference voltage, and determines an object disposed on the seat based on the second voltage.