A straight down type LED (light-emitted diode) backlight module comprises a base plate, a diffusion plate, a plurality of LEDs arranged between the base plate and the diffusion plate, and a plurality of light scattering elements arranged between the base plate and the diffusion plate, wherein the LEDs are arranged on the base plate, the light scattering elements are used for scattering light emitted by the LED, each light scattering element comprises an arc light inlet surface and a light outlet surface, a plurality of scattering structures are formed on the light outlet surface and comprise at least one first scattering structure, at least one second scattering structure or the combination of the first scattering structure and the second scattering structure, each first scattering structure is an annular groove which is arranged on the light outlet surface in an inwards-concaving way, the bottom surface of the annular groove is an inwards-concaving arc surface, and each second scattering structure is an annular wall which is arranged on the light outlet surface in an outwards-protruding way. The straight down type LED backlight module can meet the requirement of slim type design.The invention also provides an LED structure capable of scattering light emitted by an LED chip.