We consider an algebraic system seminearring, which is a generalization of both a semiring and a nearring. We define concepts of s-k-ideal of a seminearring and its fuzzy s-k-ideal as well. For a given s-ideal (resp. s-k-ideal) of a seminearring, the existence of its fuzzy s-ideal (resp. fuzzy s-k-ideal) is obtained. Further, we prove that inverse homomorphic image of a fuzzy s-k-ideal is again a fuzzy  s-k-ideal, and a homomorphic image of fuzzy s-k-ideal is again a fuzzy s-k-ideal under invariant epimorphism.