Recently, an energy-saving drive system which combines a small displacement pump with an AC servo motor or inverter motor can be frequently seen. Therefore, our company has developed small axial piston pump/motor series with a spherical valve plate using our original design and the precision processing technology. Furthermore, we have developed a compact HST as well in order to contribute to the low birthrate and longevity issue. In this report, I briefly explain the efficiency and application example of the micro pump and HST with a spherical valve plate.