The invention relates to a pile foundation structure in marine engineering, in particular to a fiber composite pile used in marine environments and a preparation method thereof; the composite pile includes a pile body and a pile tip, and an FRP reinforcement cage is arranged inside the composite pile, so that The FRP reinforcement cage includes a pile body FRP reinforcement cage and a pile tip FRP reinforcement cage. The splash area is pasted with 2 layers of FRP cloth, and the FRP cloth is at an angle of 0 to 90° to the longitudinal axis of the pile body; the present invention also provides a marine Environmental fiber composite pile preparation method, first make fiber composite pile formwork, bind FRP cage, then pour concrete, curing, then polish the splash area, brush the bottom resin, leveling treatment, apply diffuse resin, and smear on the FRP cloth Adhesive resin, and finally paste FRP cloth; the fiber composite pile in the present invention has the advantages of good ductility, good durability, light weight, etc., and can be applied to bridges and port projects.