In this paper, the problem of maximizing the secrecy capacity is studied in the wiretap channel with a hostile jammer. Considering the defective performance of the conventional Singular Value Decomposition(SVD) algorithm in the high SNR regime, we firstly propose a beamforming(BF) scheme based on the Interference Alignment(IA) to jointly eliminate the influence from the jamming signal and artificial noise. Then, in order to achieve higher secrecy capacity, a new power allocation method is derived. Finally, Monto Carlo simulations show that the proposed algorithm performs better than the conventional algorithm.