The utility model discloses an adjustable limiting positioning support. Two parallel inverted-'L'-shaped plates (3) are connected with each other by a connecting plate (4) to form a body (1) of the adjustable limiting positioning support, hoops (2) are fixed to the upper ends of the two inverted-'L'-shaped plates (3), and connecting bolts (5) are arranged at the lower ends of the two inverted-'L'-shaped plates (3); fixing blocks (6) are fixed to positions between bent positions of the lower ends of the two inverted-'L'-shaped plates (3) and are positioned above the bent positions of the lower ends of the two inverted-'L'-shaped plates (3); inner screw holes (7) are formed in the fixing blocks (6), and adjusting bolts (8) are arranged in the inner screw holes (7); locking nuts (9) sleeve the adjusting bolts (8) and are positioned on the upper end surfaces of the fixing blocks (6); limiting stoppers (10) are fixedly connected to the lower ends of the adjusting bolts (8) and are protruded out of the lower end surfaces of upper arms of the inverted-'L'-shaped plates (3). The adjustable limiting positioning support has the advantages that the limiting stoppers can be adjusted, so that uplifting amounts of positioners can be controlled, and the technical problem of insufficient uplifting amounts or excessively high uplifting amounts of existing positioners due to the fact that design requirements on distances from contact wires to positioning pipes cannot be met during site construction can be solved.