An LED lamp includes a frame, a bracket connected to the frame, two LED modules and driving modules received between the frame and the bracket, and a backplate, a reflective plate, a light guide, a diffusion plate and a cover sequentially sandwiched between the frame and the bracket. The LED modules are oriented towards two opposite lateral sides of the light guide. The light guide has a large amount of scattering dots formed on a back face thereof. The scattering dots are arranged in multiple columns. The sizes of the dots in each column are identical to each other, and the sizes of the dots in different columns gradually increase from two opposite sides towards a middle of the light guide.