Due to the global warming and resulting environmental regulations, the use of rechargeable lithium batteries is rapidly growing. However, the current lithium-ion batteries (LIBs) employing liquid electrolytes have a safety concern, since the liquid electrolytes are highly flammable, which can lead to a fire or an explosion under abnormal conditions. Accordingly, all-solid-state lithium batteries are considered promising alternatives to current LIBs. Among various types of solid electrolytes, sulfide-based electrolytes exhibit high ionic conductivities at room temperature, comparable with those of liquid electrolytes. In order to improve the energy density of the solid-state batteries, it is essential to increase the loading of active mass in the composite cathode. In this study, we tried to increase the active mass loading by investigating the optimum conditions with respect to types of active materials. As a result, we could obtain good cycling performance of the sulfide-based all-solid-state lithium batteries employing the composite cathode with high active mass loading (> 4.5 mAh cm^-2).