An improved molding structure of a bike brake shoe including a pre-assembly of metal base comprised of a disk, a cover and an adjustment base before being injection molded into a brake shoe by injection is characterized by that an opening of the disk forms a separation chamber when closed up with the cover to prevent seepage of glue solution in the course of molding and to allow the adjustment base in the chamber to have its rod merely slacken and protruding out of the bottom of the disk for the brake shoe to permit easy adjustment by sliding, and thus better braking effect.