Abstract: The presently disclosed sports board stringer system provides for a flexible, high tensile strength, waterproof structural support for any sports board. The stringer system itself comprises one or more lengths of random, non-woven, thermoplastic web fiber composite material, bonded by resin, and inserted or formed into the core of the board. In alternate embodiments, wood or other materials can make up additional layers which are also bonded to the fiber composite by resin. Additionally, stringers of the present invention can be constructed in different layouts, with more than one width of stringer section at any section of the board. Also, multiple stringers could be located in different places throughout a board. The stringer material, including all layers, can be constructed and transported in sheets and then locally cut and sanded to any length or thickness.