The invention relates to a dry gear cutting technology of a helical bevel gear, comprising the following steps: adopting round bar steel stamping with the outer diameter of 60-180mm for shaping, selecting a K-class superfine hard alloy cutter, heating a workpiece to 920-950 DEG C, preserving the temperature for 2-4h, cooling the temperature to 540-680 DEG C by air, preserving the temperature for 2-4h, cooling naturally to room temperature, lathing the workpiece after normalizing treatment to the required dimension of the gear, performing gear cutting, lathing, detecting and warehousing. The invention completely adopts dry gear cutting without the need of cutting oil and surface cleaning before heat treatment, thus reducing industrial pollution, improving processing efficiency, lowering production cost, having high precision of product gear cutting processing and short technology flow.