A process for producing a rod-form silica from a silicic acid ester according to a sol-gel process, which silica has a rod-form having a high aspect ratio and is advantageously used as a filler for resin sealants for semiconductors, is provided, which process comprises adding 35 to 150 parts by weight of a sol of a silicic acid ester to 100 parts by weight of a hydrophobic medium to form an emulsion, subjecting the emulsion to a temperature rise at two stages, the first temperature rise being by 5.degree. to 30.degree. C. at a rate of 10.degree. to 200.degree. C./min. or less and the second temperature rise being by 3.degree. to 20.degree. C. at a rate of 0.5.degree. to 10.degree. C./min., to form a rod-form silica.