The invention provides a portable spinal orthotic backrest. The portable spinal orthotic backrest comprises a back support plate which is integrally formed by a plastic material, and the back support sheet comprises an upper portion and a lower portion from top to bottom in the vertical direction the inside radian of the central longitudinal section of the upper portion in the vertical direction is consistent with the radian of the thoracic vertebrae of a human body, and the inside radian of the transverse section of the upper portion in the horizontal direction is consistent with the radian of the human back corresponding to the thoracic vertebrae in the horizontal direction and the inside radian of the central longitudinal section of the lower portion in the vertical direction is consistent with the radian of the lumbar vertebrae of the human body, and the inside radian of the transverse section of the lower portion in the horizontal direction is consistent with the radian of the human back corresponding to the lumbar vertebrae in the horizontal direction. The backrest not only is simple in structure but also does not occupy space the back support plate can correctly and integrally support the thoracic vertebrae and the lumbar vertebrae of a user and through a waist and back muscle relaxation mechanism, the purpose of fine-tuning the thoracic vertebrae and the lumbar vertebrae to the correct positions is further achieved.
