In this paper, we establish a generalization of fundamental homomorphism theorem in BCK-algebras by using fuzzy BCK-filters. We prove that if ${mu}$. (resp. v) is a fuzzy BCK-filter of abounded BCK-algebra X (resp. Y), then $frac{X{ imes}Y}{{mu}{ imes}v}{approxeq}X/{mu}{ imes}Y/v;;and;if;{mu}$ and F is a BCK-filter in a bounded BCK-algebra X such that $F/{mu}$ is a BCK-filter of $X/{mu}$, then $frac{X/{mu}}{F/{mu}}{approxeq}X/F$.