By the well-known large and small blocks parting method for dependent situations, we establish the asymptotic normality of the Empirical Distribution Function under Negatively Associated Sequences.As its application in reliablity problems,a natural estimate (?)_n(x) for the survival function (?)(x)=P(X>x)is proposed,and the asymptotic normality of n~(1/2)[(?)_n(x)-(?)(x)]is established.