In this paper we introduce the notion of a fuzzy polynomial ideal α x of a polynomial ring R[x] induced by a fuzzy ideal α of a ring R, and obtain an isomorphism theorem of a ring of fuzzy cosets of α x . It is shown that a fuzzy ideal α of a ring is fuzzy prime if and only if α x is a fuzzy prime ideal of R [x]. Moreover, we show that if α x is a fuzzy maximal ideal of R[x], then α is a fuzzy maximal ideal of R.