The invention discloses a gallium nitride light emitting diode and a preparation method thereof. The gallium nitride light emitting diode comprises pins, dustproof sleeves, sealing rings, a fixed base, bottom plates, fastening springs, a baffle, fixed clamping blocks, a packaging body, a protection sleeve, a first ceramic layer, a first anti-static layer, a heat dissipation layer, a waterproof layer, a second anti-static layer, a second ceramic layer, a diode body, a P type electrode, a GaN: Mg layer, an InGaN multi-quantum well, a GaN: Si layer, a GaN buffer layer, a sapphire substrate, an Ntype electrode, limiting springs, a mounting base, limiting blocks, a mounting partition plate and heat conducting adhesive; the pins are mounted on the two sides of the packaging body through the fixed base, and the outer sides of the pins are packaged with the dustproof sleeves; the baffle is mounted in the fixed base through a bolt; two bottom plates are mounted on the two sides of the top of the baffle through bolts; and the fastening springs are mounted on one sides of the bottom plates through buckles. The light emitting diode is convenient and quick to mount, stable in structure, has certain impact resistance and effectively improves use convenience.