The invention discloses a T structure closure pouring method for a mountainous-area high-pier large-span continuous rigid-frame bridge. Before T structure closure pouring, weights are loaded at the cantilever ends of T structures to enable the cantilever ends of the two sides of T structure mid-span enclose sections to generate large longitudinal horizontal displacement towards to the two side-span directions so as to compensate shrinkage and creep and horizontal displacement generated due to later-period whole temperature reduction; the high-pier large-span characteristics are combined, adverse influence, on the continuous rigid-frame bridge internal force and deflection, of concrete shrinkage, creep and the temperature effect which are caused due to the effect of long-term load is reduced, and mid-span mid span bottom bending caused due to the influence of concrete shrinkage and creep is avoided; and weight bodies can obtain materials from local sources, pushing is not needed, simple and feasible effects are achieved, construction is convenient, safety is high, original side span cast-in-situ sections and enclose sections adopt hanging baskets for pouring till pouring is conducted to supporting seats, supporting engineering is reduced, after mid-span enclosure, in side span cast-in-situ, the whole rigidity is large, deformation control is good, and construction is easy.