Abstract: Shape memory alloys（SMAs）have great application potential in microactuators and mini-ature actuators, because of their large power density and recoverable strain, low actuating voltage good biology compatibility, etc. Present application studies on microactuators（such as micro-drug-systems, microvalves, micropumps, microgrippers, etc.）actuated by TiNi-based SMA wires, sheets, and thin films, are reviewed. The existing problems in the applications of microactuators are discussed, as well as the methods to overcome these problems.