An apparatus for fixing bad posture includes a support rod, multiple length-adjustable straps, and multiple strap-attachment points. The apparatus for fixing bad posture prevents the user from slouching by affixing the support rod to the user's back with the straps. The support rod is a rigid member that is placed against a user's back. The support rod has a rod body, a mounting face, and a bracing face. The rod body is the structural component of the support rod. The bracing face and mounting face are positioned on opposite lateral surfaces of the rod body. Thus positioned, the bracing face is pressed against the user's back when correcting posture. The strap-attachment points are connection mechanisms for the length-adjustable straps that are distributed along the length of the support rod. As such, each of the length-adjustable straps is attached to the support rod by a corresponding strap-attachment point.