To provide a method for conducting such reinforcement as to enhance original strength while keeping concrete installed in a standing manner when a crack is developed in a concrete pole.

A grain-of-sand injecting hole 1 and a vacuum suction hole 2 are pierced in the upper part of the concrete pole P. The grains of sand are vacuum-sucked in through the hole 2 while being blown in through the hole 1 by air, and the blowing of the grains of the sand is stopped when the grains of the sand come to be sucked in through the hole 2. An instantaneous consolidation agent 4 is injected superficially into the upper part of the sand through the hole l so as to cut off a sand layer from an upper air section. The hole 1 is closed by filling. The agent 4 is vacuum-sucked in through the hole 2 while being injected through a consolidation-agent injecting hole 3 pierced in the lower part of the concrete pole P, and the injection of the agent 4 is stopped during the appearance of the agent 4 through the hole 2. The agent 4 makes the sand consolidated so as to reinforce the concrete pole P. The mixing of polypropylene fibers into the sand makes the grains of the sand coupled together for the purpose of enhancing the strength.