The invention discloses a cast-in-place pile hole forming and side wall grouting construction method for a coral sand foundation. The method is characterized in that construction of hole forming of acast-in-place pile casing pipe is carried out by adopting a vibration and static pressure alternate operation method, pile side grouting is carried out while the steel casing pipe is pulled out, and specific construction comprises the steps of hole forming, hanging and placing a reinforcement cage, grouting the casing pipe, secondary hole cleaning, cast-in-place pile pouring, pulling out the steelcasing pipe, side wall grouting and the like. Compared with the prior art, the method has the advantages that the pile forming reliability and the pile foundation bearing capacity are high, the soilbody disturbance is effectively reduced, the particle crushing degree is reduced, the pile side friction resistance is improved, the problems of hole forming difficulty and low side resistance of thecoral sand foundation are well solved, the steel casing pipe can be recycled, the engineering cost is greatly reduced, and the method is green and environment-friendly, and has good environmental protection benefits and popularization prospects.