Fluorine-containing synthetic quartz glass is produced by feeding silica-forming material, hydrogen, and oxygen gases from a burner to a reaction zone, flame hydrolyzing the silica-forming material in the reaction zone to form particles of silica, depositing the silica particles on a rotatable substrate in the reaction zone to form a porous silica matrix, and heating and vitrifying the porous silica matrix in a fluorine compound gas-containing atmosphere. During formation of the porous silica matrix, the angle between the center axes of the silica matrix and the silica-forming reactant flame from the burner is adjusted to 90 120.degree. so that the porous silica matrix has a density of 0.1 1.0 g/cm.sup.3 with a narrow distribution within 0.1 g/cm.sup.3. The resulting quartz glass has a high transmittance to light in the vacuum ultraviolet region below 200 nm.