An inspection method and apparatus of laser crystallized silicons in the low-temperature poly Si (LTPS) process. The crystalline quality is inspected by using a visible light source to irradiate the surface of the poly Si and examining the variations of the reflected light caused by the protrusion arrangement at the surface of the poly Si. This method can be adopted on the poly Si samples prepared by the line scanning of the excimer laser annealing (ELA) technology.