The invention relates to the field of lighting lamps, and discloses an LED (light emitting diode) street lamp. The LED street lamp comprises an aluminium shell, a support, a power source and multiple modules, wherein the aluminium shell comprises two arc-like fixed pieces, a beam and a dust-blocking cover; and the dust-blocking cover is provided with two parallel square holes, the power source connected with the modules is positioned in the arc-like fixed pieces, and a water seepage gap is reserved between the adjacent modules. The LED street lamp has the advantages of novel structure, good heat dissipation effect, long service life, reasonable modular structure, and the same sending direction of forced light rays.