Traditional AEC’s performance is restricted when using double-talk detector to determine the double- talk and single-talk scenarios. Blind source separation signal model is a full duplex model with both far-end and near-end signals, so AEC based on BSS does not need the double-talk detector. This paper adopts auxiliary function based independent component analysis algorithm to realize acoustic echo cancellation in frequency domain. The object function of Aux-ICA is minimizing the mutual information, and the auxiliary function technique is used for the optimization. Simulation results show that this method has lower computational complexity and better acoustic echo cancellation performance in the continuous double-talk scenarios.