To provide a method for producing an optical fiber preform stabilizable of characteristics of an optical fiber by making the growth rate of the optical fiber preform in an axial direction to suppress variations in ΔN (specific refractive index difference).

In the method for producing an optical fiber preform, the supply flow rate of H2, which is a combustible gas, is controlled so that the growth rate of a glass fine particle deposit in an axial direction becomes constant instead of adapting to changes in the growth rate, and supply flow rate of GeCl4, which is an additive, is controlled so as to be in proportion to that of H2.