In the 21st-century, it is very important to enhance the capability of obtaining information and controlling the microsystems to realize the SOC (System-On-Chip). One of key issues to the microsystems is MEMS (Micro-Electro-Mechanical Systems) technology for microsensors, microactuators and NanoPhotonics. We are conducting a lot of researches on the systematic design, fabrication process, micro packaging and experimental characterization of the MEMS devices for optical applications (matrix switch, variable attenuator, tunable filter for telecommunications), nano data storages and other future applications.