Abstract
In this paper we shall introduce the notion of rough prime ideals and rough fuzzy prime ideals in LA-semigroups. We proved that the lower and the upper approximation of a prime ideal is a prime ideal and we also proved that a fuzzy subset f of an LA-semigroup S is a fuzzy prime ideal of S iff f(lambda) not equal empty set (f(lambda)(s) not equal empty set) is a prime ideal of S for every lambda is an element of [0, 1].