Abstract: The absorbing performance of a wedge absorber with recavitytor is studied.The theoretical method for calculating the absorption coefficient of the absorber is provided and the relationship between the absorption coefficient and frequencies is given by computer simulation.The results showed that the absorption performance of this kind of absorber is better than normal wedge absorbers in low frequency and it keeps good absorbing performance in high frequency.The performance in low frequency can be improved by changing the size and structure of the resonator.