The invention discloses an efficiently-cooled LED street lamp which comprises a lamp post, a lamp body and an LED light source. The lamp body comprises an upper cover and a transparent lower cover. The upper cover is fixed to the lamp post. The top of the upper cover is provided with a plurality of frustum-shaped protrusions. The top of each protrusion is provided with a screw hole and an annular protruding strip. The LED light source is composed of a plurality of independent LED modules. Each LED module comprises a cooler and an LED light emitting assembly fixedly arranged at the bottom of the cooler. Each cooler comprises a body and cooling fins arranged on the top of the body, wherein the bottom of the body is provided with a cylindrical boss and an annular groove, the boss is arranged at the center of the bottom of the body, the radial edge of the boss is provided with a thread matched with the screw hole, the corresponding light emitting assembly is arranged at the bottom of the boss, and the annular groove surrounds the radial edge of the boss and is matched with the corresponding annular protruding strip. The LED street lamp is good in universality and replaceability, low in maintenance cost and good in cooling effect.