Searching for victims in narrow gaps and shoring up pieces of debris to secure space are tasks encountered in disaster rescue operations. The authors have developed high-strength robot joints for microrobots to be used in such situations. The joints developed are of three types – swivel joint, extension joint, and strut joint – all having an outer diameter of 60mm and driven by a 21MPa hydraulic system. This paper presents the system configuration of a power microrobot for traveling and searching inside debris, then describes the mechanisms and controls of the three developed joints. This study thereby demonstrates the possibility of realizing a microrobot capable of maneuvering within narrow gaps and shoring debris to secure space. The microrobot weighs approximately 25 or 35kg (including the hydraulic unit), is driven by a 100V power supply, with 300W power consumption, and has an outer diameter of 60mm and length of about 1m.