The invention concerns a fuel tank (1) of thermoplastic material comprising at least one peripherally extending seam (3) in the form of a welded or squeeze seam, at least one filling opening, air intake and venting means and means for delivering and removing fuel in relation to an internal combustion engine of a motor vehicle, wherein the fuel tank has at least one lead-through means (5) for lines which are to be passed out of the tank. The fuel tank (1) according to the invention is distinguished in that the lead-through means (5) passes through the seam (3) of the tank and extends at an angle relative to the course of the seam (3).