The invention discloses a steel pile casing anti-falling platform for underwater bridge foundation construction and a construction method of the steel casing anti-falling platform, and relates to thefield of bridge construction. The anti-falling platform comprises a plurality of steel pipe piles, a drilling platform, a plurality of third distribution beams and an anti-falling component; a plurality of first distribution beams are arranged on the steel pipe piles; the steel pipe piles are inserted into water; the drilling platform comprises a panel and a plurality of second distribution beams;the second distribution beams are arranged on the first distribution beams; the plurality of second distribution beams are positioned on the same horizontal plane; the panel is arranged on the planewhere the second distribution beams are located; a plurality of positioning holes for accommodating the steel pile casings are formed in the panel; the third distribution beams are arranged at the positioning holes and configured to be close to the steel pile casings when the steel pile casings are arranged in the positioning holes; the anti-falling component comprises a connecting piece and a supporting piece; the connecting piece is used for being arranged in the circumferential direction of the steel pile casings; the supporting piece is fixed to the third distribution beams; and the supporting piece and the connecting piece are fixed in a matched mode. According to the invention, the phenomenon that the steel pile casing falls or deviates can be avoided.