A method for fabricating an LED chip is provided. Firstly, a SiO2 pattern layer is formed on a top surface of a substrate. Then, lighting structures are grown on a portion of the top surface of substrate without the SiO2 pattern layer thereon. Thereafter, the SiO2 pattern layer is removed by wet etching to form spaces between bottoms of the lighting structures and substrate. An etching solution is used to permeate into the spaces and etch the lighting structures from the bottoms thereof, whereby the lighting structures each with a trapezoid shape is formed. Sidewalls of each of the lighting structures are inclined inwardly along a top-to-bottom direction.