To provide a fabrication method for a porous glass base material for optical fiber, the method including performing deposition of glass fine particles generated by using a burner for glass fine particle synthesis to form a porous glass base material, and heating this porous glass base material to be transformed into transparent glass to obtain a glass base material hardly containing any air bubbles. Provided is a fabrication method for a porous glass base material for optical fiber by depositing glass fine particles, which is generated in flame formed by ejecting a glass raw material gas and a combustible gas from a burner, on a rotating starting material, in which the burner continuously ejects inert gas for at least a predetermined period immediately after the end of the deposition of the glass fine particles.