Ti-Ni shape memory thin films are expected to be applied for microactuators due to the great advantages such as large shape recovery force and strain. In this study, a Ti-Ni thin film was deposited on a Si substrate with SiO, surface by using the radio-frequency magnetron sputtering method. A diaphragm microactuator was fabricated by applying the well-known Si photoetching method, and a heat-treatment was carried out in order to acquire shape memory effect. The shape of the diaphragm was square with the width of 560mum, The Ti-Ni diaphragm was convex in the martensite phase and flat in the parent phase, and the shape change occurred repeatedly by cooling and heating, In order to evaluate the dynamic motion of the diaphragm microactuator, the three-dimensional shape analysis was performed with varying experimental parameters such as frequency and current. It is concluded that the displacement of the Ti-Ni diaphragm actuator is changed by changing the current and/or the frequency.