The invention relates to a manufacturing technique of electronic grade red phosphorus, which comprises obtaining high-purity phosphorus trichloride after distilling and rectifying analytically pure phosphorus trichloride, inletting high-purity hydrogen which is used as a reductant into a quartz diffusion furnace of phosphorus trichloride to deacidize in heating condition, absorbing phosphorus steam with hot water, collecting yellow phosphorus and obtaining high-purity yellow phosphorus via filtration washing, then placing the yellow phosphorus into a distinctive conversion heater, heating theconversion heater and adding inert gas conservation for protection and obtaining electronic grade red phosphorus products. The invention has the advantages of simple craft and stable quality. The products can completely satisfy quality requirements of semi-conductor industry.