In this study, the concept of fuzzy sub KS-semigroup generated by a given fuzzy set is provided. It is shown that the sum of two fuzzy sub KS-semigroup of a KS-semigroup $X$ is the fuzzy sub KS-semigroup generated by their union and the set of all fuzzy sub KS-semigroup of a given KS-semigroup forms a complete lattice. Consequently, it is establish that the collection of all fuzzy sub KS-semigroup, having the same value at zero, of $X$ constitute a complete sublattice of the lattice of all fuzzy sub KS-semigroup.