The present invention relates to a heat treatment device for heat-treating the inner surface of a braid for reinforcing a hollow fiber membrane for water treatment and, more particularly, to a device for heat-treating the inner surface of a braid for reinforcing a hollow fiber membrane for water treatment and a braid manufactured using the same, wherein the device is configured to densify the texture of the inner surface of the braid, thereby increasing the inner diameter of the braid, the device is configured to improve the roundness of the inner and outer diameters and to increase the pressure-resistant strength, thereby improving the physical characteristics of the hollow fiber reinforcement membrane, the device is configured to improve the filtering reliability and the water permeability, and the device is configured to extend the service life and to reduce economic costs.
