A tube fitting is provided which is able to be easily attached even in a narrow attaching place. The tube fitting 1 includes one or more fitting parts 4 to be connected to an external tube formed at one end of a main body 2 and a screw part for attachment 3 formed at another end of the main body 2, wherein fluid passes through an inside part thereof and wherein the screw part for attachment 3 has, at its external circumference, screw threads and, in its inside part, a tool connecting part into which a non-inverse and inverse rotation tool to rotate the screw part for attachment 3 non-inversely and inversely is allowed to be fitted, and a pipe path through which fluid passes.