A method for connecting pipe members for an endoscope includes the steps of arranging two pipe members each made of a corrosion-resistant alloy material by fitting one in another so that a passage is defined through the two pipe members, jetting inert gas toward an exterior of an area at which the two pipe members are to be connected, injecting inert gas through the passage defined through the two pipe members, and connecting the two pipes by laser welding such that a laser beam is irradiated toward the exterior of the area at which the two pipe members are to be connected with jetting the inert gas toward the exterior of the area at which the two pipe members are to be connected and injecting the inert gas through the passage defined by through the two pipe members.