A laser crystallization system and a method of manufacturing a display apparatus using the laser crystallization system are disclosed. In one embodiment, the system includes i) a mother substrate in which first, second, and third display regions and ii) a stage for supporting the mother substrate and moving in first and second directions perpendicular to each other. The embodiment also includes i) a first laser irradiation unit for irradiating a first laser beam having a width greater than or identical to a width of a side of one of the first, second, and third display regions in the first direction and ii) a second laser irradiation unit spaced apart from the first laser irradiation unit and irradiating a second laser beam having a width greater than or identical to the width of the one side in the first direction.