The invention discloses a correction method for a capacitive material level sensing device. The method is applied to measurement of a drum tank. The correction method comprises following steps: generating a measuring signal by a measuring signal generation circuit to measure the drum tank; transmitting a sensing signal to a control unit by a sensing circuit based on a measuring result measured by the measuring signal; determining whether the sensing signal is within the effective range by a control unit according to the sensing signal; setting a total capacitance value corresponding to the sensing signal by the control unit as measuring reference value if the control unit determines that the sensing signal is within the effective range; and controlling the measuring signal generation circuit by the control unit to adjust measuring frequency of the measuring signal if the control unit determines that the sensing signal is not within the effective range. The method is capable of automatically correcting the capacitive material level sensing device.