Digital holography allows recording the hologram using digitally imaging devices such as CCD, and reconstructing the
holographic image by numerically simulating the diffraction of the hologram. Its main advantages are by which one can
directly obtain the complex amplitude distribution of the object field, so that more impersonally measure the detail
information of the object field, such as the distribution of the refractive index changing in crystals induced by light
irradiation, deformation of the object surface, particle distribution, as well as acoustic field, flow field and temperature
distribution in air. In this paper, we summarize the principle and some of our experimental results on the applications of
digital holography in visualized measurement of acoustic standing wave (acoustic levitation field), plasma plume and
water flow (Karman vortex street) fields.