Method for producing sulfide solid electrolyte

A method for producing a sulfide solid electrolyte according to the present invention comprises: a step for mixing a lithium (Li) element source, a phosphorus (P) element source and a sulfur (S) element source together to produce a starting material composition; a step for firing the starting material composition to produce the sulfide; a step for pulverizing a slurry comprising a solvent having a fluorine atom and the sulfide; and a step for drying the slurry. It is preferred that the concentration of the sulfide in the slurry is 3 to 40% by mass inclusive. It is also preferred that the step for pulverizing the slurry is a step for pulverizing the sulfide in a dry mode and mixing the sulfide that has been dried in a dry mode with the solvent to prepare the slurry.