A nonvolatile ferroelectric memory device using a silicon substrate includes an insulating layer formed in an etching region of the silicon substrate, a bottom word line formed in the insulating layer so as to be enclosed by the insulating layer, a floating channel layer formed over the bottom word line, an impurity layer formed at both ends of the floating channel layer and including a source region formed over the insulating layer and a drain region formed over the silicon substrate, a ferroelectric layer formed over the floating channel layer, and a word line formed over the ferroelectric layer.