The utility model relates to a summer safety helmet, which comprises a helmet body; and one or a plurality of tapered holes is/ are arranged on the helmet body. The smaller opening of the tapered hole faces towards the exterior of the helmet body. The safety helmet further comprises a helmet brim, and the helmet brim is removably arranged on the edge of the helmet body. The tapered hole is arranged on the helmet body, thereby ensuring ventilation and meeting safety requirement at the same time. The helmet brim arranged on the helmet body can solves the problem that linemen often and difficultly observe a circuit due to dazzling sunshine when working in summer, and the skin of the linemen is broken by the sunshine as a result of exposing the necks of the linemen out. The helmet brim is removable, and therefore, the safety helmet can be used indoors or in the period of non-high temperature.