Disclosed is a method for producing a solid electrolyte material-containing sheet having good strength. The method for producing a solid electrolyte material-containing sheet is characterized by comprising a preparation step of preparing a raw material composition which contains a sulfide solid electrolyte material, a monomer or oligomer having a double bond, and a binder composition containing aradical polymerization initiator; a coating step of forming a sheet-like composition by applying the raw material composition; and a polymerization step of subjecting the sheet-like composition to a radical polymerization process.