With the aging of the population increase, the need of hearing aids is increasing, along with the wide application of digital signal processing technology, applied to adaptive echo cancellation algorithms in digital hearing aid has been significantly improved and developed. This article will to tell echo cancelation principle, to introduce several common algorithms, such as RLS algorithm, LMS algorithm and NLMS algorithm, puts forward a kind of algorithm which is a combination of NLMS algorithm, and BLMS algorithm, named NBLMS_M-K. Finally, discuss the future development of algorithm.