The invention relates to a reinforced concrete bridge component tension anti-unstability device which comprises a stabilizing beam, wherein the stabilizing beam is connected with two left and right tying beams; fixing frames are arranged at both ends of the stabilizing beam; the fixing frames are fixed on the tying beams; a fixing structure for limiting longitudinal movement of the stabilizing beam is arranged between the stabilizing beam and the fixing frame. The device has the beneficial effects that two independent tying beams are integrally connected by using the stabilizing beam, constraint conditions are added, the free lengths of the tying beams are greatly reduced, the slenderness ratio is reduced, and the stability is improved; the stabilizing beam and the tying beams are both limited in upper and lower, left and right and front and back directions through the fixing frames and baffle components, reliability in connection is achieved, the stabilizing beam is conveniently mounted and dismounted, and the stabilizing beam consists of bailey trusses through assembling and has the advantages of being rapid to assemble, easy in material obtaining, low in cost and rapid in effecttaking.