Disclosed is a tube-propelling apparatus for a tube bending machine. The apparatus comprises a main tube-propelling base mounted on a slide rail mechanism of a tube bending machine tool, wherein a penetrating hole though which both a fixing sleeve and a core rod pass is provided on the main tube-propelling base, the rear end of the fixing sleeve is fixed in the penetrating hole, and the front end of the fixing sleeve is provided with a tube clamping apparatus. The propelling apparatus further comprises a surplus material auxiliary propelling base mounted on the slide rail mechanism of the tube bending machine tool, wherein the surplus material auxiliary propelling base is provided with a through-hole coaxial with the penetrating hole of the main tube-propelling base. An auxiliary pushing sleeve is mounted in the through-hole, and the core rod passes through the auxiliary pushing sleeve. Meanwhile, the auxiliary pushing sleeve is sheathed in the fixing sleeve and the front end of the auxiliary pushing sleeve is provided with a propelling head engaging with a tube. The tube-propelling apparatus has a simple and rational structure, and can fully utilize surplus material.