An apparatus and method for enhancing the accuracy of a sensor signal are provided. The apparatus includes: a low-pass filter (LPF) that filters the sensor signal and outputs a low-frequency sensor signal; an operation determination unit that determines whether the sensor is not in operation; a bias estimating unit that estimates bias included in the low frequency sensor signal output from the LPF according to the output of the determination unit; and a subtractor that subtracts the estimated bias from the low frequency sensor signal according to the output of the operation determination unit.