The invention discloses an overall composite towing beam arching structure for a railway steel truss girder cable-stayed bridge, which aims to uniformly transfer a cable force to a main truss structure, has high integrity without generating greater stress concentration phenomenon at key parts such as a welding seam and the like, and improves the anti-fatigue performance of the structure. The structure comprises a pair of overall arch plates (11 and 12) and a steel anchor box (20), wherein the pair of overall arch plates (11 and 12) are formed by extending upwards directly from node plates on the two sides of the top chord of a main truss; the steel anchor box (20) is arranged between the upper parts of the pair of overall arch plates (11 and 12) and is fixed with the upper parts of the overall arch plates (11 and 12); a steel sleeve tube (N7) through which a stayed-cable can pass is fixedly arranged in the steel anchor (20); and the stayed-cable axis of the steel sleeve tube (N7) is crossed with the central line (1) of a node of the main truss, an upper chord system line (2) and a diagonal web member system line (3).