Based on brief discussion of basic LMS,by constructing a nonlinear function between the step factor μ and the error signal e(n) ,a new variable step-size LMS algorithm is proposed,along with the performance analysis with regard to different parameters.The algorithm,though adjusting the step size parameters,makes the weight vector optimal,thus improves effectively the convergence rate and steady-state error performance.The theoretical analysis and simulation results shows that this algorithm,as is of compared with the basic LMS algorithms and some similar variable step-size algorithms,faster convergence speed and smaller steady-state error.This further indicates that this new algorithm is superior to other algorithms.