The amorphous-silica particle having 0.1 0.7 .mu.m of the average particle diameter, 5 30 m.sup.2/g of the specific surface area, less than 40% of the dispersion coefficient, and 20 .mu.C/m.sup.2 of the absolute value of the triboelectrostatic charge, can be obtained, by setting flame temperature to more than melting point of silica, raising the silica concentration in a flame, and staying the generated silica particle in the flame for a short time to be grew up. Since this silica particle has a particle shape being near a true sphere, and a particle size of said particle is remarkably uniform, so it is suitable for a filler of a semiconductor sealing agent or various materials, etc. In addition, since said particle has strong electrification, it is also suitable for an outer or an inner additional agent of a toner for an electronic photograph, a photo conductor material for a electronic photograph, and a material of an electric charge transportation layer, etc.