A resin-made fuel tank includes: a resin-made fuel tank body provided by bonding an upper half body and a lower half body to each other; and a barrier sheet layer provided on an inner surface of the fuel tank body and provided for reducing permeation of fuel from the fuel tank body, wherein an edge of the barrier sheet layer is disposed in a vicinity of an upper bonding surface and a lower bonding surface where the upper half body and the lower half body are bonded to each other in a mating manner, the edge has a bent portion which bends toward an outside of the fuel tank body, and the bent portion is embedded in the fuel tank body at a position spaced apart from the upper bonding surface and the lower bonding surface.