METHOD FOR PRODUCING SULFIDE SOLID ELECTROLYTE

Provided is a method for producing a sulfide solid electrolyte having a high purity as side reaction hardly occurs, and having a high ionic conductivity, in a simplified manner. The method is for producing a sulfide solid electrolyte containing a lithium atom, a sulfur atom, a phosphorus atom and a halogen atom, comprising separately preparing a complex (1) containing a sulfide that contains a lithium atom, a sulfur atom and a phosphorus atom, as a constituent element, and a complex (2) containing a halide that contains a lithium atom and a halogen atom, as a constituent element, and mixing the complex (1) and the complex (2).