The invention discloses a pre-stressing reinforced and widened bridge structure, which comprises an old bridge, a widening beam I and a widening beam II, wherein the widening beam I and the widening beam II are parallelly and respectively positioned on the two sides of the old bridge and are rigidly connected in the transverse direction with the old bridge; the two ends of a pre-stressing rope or a pre-stressing rib are transversely and respectively arranged outward and are upwards inclined, extended and anchored on the widening beam I and the widening beam II; and the pre-stressing rope or the pre-stressing rib is acted on the old bridge through a steering device. While being widened, the old bridge can be reinforced by the structure, the stress between the newly added part and the old bridge is balanced, the occurrence and the development of defects of the old bridge can be effectively inhibited, the structure and the construction of the bridge are relatively simple, the structure of the old bridge is not damaged, the structural performance is reliable after the old bridge is widened and reinforced, the construction period is relatively short, the influence on road traffic is relatively small, the damage to natural environment and the adverse influence on society when the old bridge is demolished are avoided, and very good comprehensive technical, economic and social benefits are achieved.