This study introduces service robots to improve restaurant industry labor productivity because restaurant productivity is the lowest among service industries. Furthermore, this study represents an attempt to improve robot productivity because low robot productivity is the main hindrance to robot introduction into service industries. Service robot systems developed based on AGV robot systems were incorporated into operations of an actual restaurant. Staff operations changed. The AGV replaced conveyance operations to reduce staff work loads. Moreover, the AGV systems are refined to increase AGV work loads: the number of AGV battery chargers was increased to avoid electric battery power shortages, AGV boards were changed from fixed type to removable type. Moving patterns increased from 1 to 4 to adopt AGV operation for restaurant operation situation changes. Results indicate that the system redesign improves labor productivity. It reduces working time and increases service quality. Furthermore, the AGV system refinement enhances robot productivity: in fact, the total AGV daily moving distance was doubled.