The invention relates to the technical field of lighting, in particular to a smart street lamp. The smart street lamp comprises a lamp post, a lamp head is fixed to the top of the lamp post through asupporting pillar and is of a semi-spherical structure, a solar panel is laid on the spherical surface of the lamp head, a light source plate is arranged on a lower plane of the lamp head, and three vertical slide grooves are formed in a main lamp post body at intervals and communicated with the interior of the lamp post; a lead screw is arranged in the center inside the lamp post and sleeved witha nut ring, connecting rods are equidistantly arranged on the nut ring and penetrate out of the slide grooves respectively, and projection lamps are arranged on the connecting rods. Compared with theprior art, the smart street lamp has the advantages of being simple in structure, high in automated and intelligent degree, and capable of meeting the development demands of smart cities and accelerating the development of the smart cities.