The invention relates to a fault judgment and filter processing method for a FADS (Flush Air Data Sensing) system of an aircraft. The method comprises the following steps: 1) establishing a FADS system equation and a measurement equation, namely assuming that the aim of FADS data resolving is to obtain a given state variable X, and establishing the FADS system equation according to the characteristics of the variable; assuming that m pressure measuring holes are adopted by FADS, and establishing the measurement equation by taking the difference between the pressure of the pressure measuring holes and an inertia indicated pressure as the measurement quantity; 2) performing FADS pressure fault judgment, judging whether each measuring pressure of FADS is reasonable by combining the inertia indicated pressure with respect to the pressure output of each pressure measuring hole of the FADS, if met, considering that pressure measurement of the pressure measuring holes is reasonable, otherwise judging that pressure measuring fault occurs; 3) performing time update and measurement update during sequential filtering according to the pressure fault judgment result of FADS. According to the method disclosed by the invention, rationality judgment of the FADS measured pressure is realized, the system reconstruction can be reduced by adopting the sequential filtering processing method when the fault occurs at the FADS pressure measuring hole, the calculated amount is small, and a support is provided for FADS data resolving.