The invention discloses a screen mesh yarn feeding device of a fishnet braider. The screen mesh yarn feeding device of the fishnet braider comprises a strip-shaped yarn feeding substrate, wherein a pair of tile-shaped locking sleeve sheets is arranged at the tail part of the yarn feeding substrate; the tail parts of the locking sleeve sheets are respectively connected with a connecting flange; a connecting through hole is formed in each connecting flange; a strip-shaped perforative adjusting hole is formed at the head of the yarn feeding substrate; limiting yarn column arrays formed by limiting yarn columns are arranged at the upper surface of the middle part of the yarn feeding substrate; the limiting yarn column arrays are respectively positioned at two sides of the yarn feeding substrate. According to the screen mesh feeding device of the fishnet braider, by using the adjusting hole at the head of the yarn feeding substrate and the limiting yarn column arrays at the middle part of the feeding substrate, a user can yarn nylon yarns through the adjusting hole and clamp the yarns between the liming line columns; finally, the user rotates the locking sleeve sheets to tension the yarns so as to finish screen mesh yarn feeding; the operation is simple and convenient.