A metal element-containing sulfide solid electrolyte may suppress H2S generation. Such a metal element-containing sulfide solid electrolyte may include a lithium element, a sulfur element, a phosphorus element, a halogen element, and at least one metal element selected from metal elements of Groups 3 to 12 and Period 4 or higher of the Periodic Table, in which the molar ratio of the lithium element to the phosphorus element (Li/P) is 2.4 or more and 12 or less, and the molar ratio of the sulfur element to the phosphorus element (S/P) is 3.7 or more and 12 or less.