In order to obtain more comprehensive three-dimensional (3-D) deformation data, improve the flexibility and precision of 3-D deformation measurement, and describe the real-time displacement of various points in the measurement scope, we researched speckle methods in this field. First, we expounded basic theories of speckle technique and elaborated on several important aspects of 3-D measurement, including camera calibration, images matching, and 3-D coordinate and displacement calculation. Then, we established the relevant mathematical models and developed a corresponding measurement and analysis software, XJTUDIC. Aided with the appropriate hardware devices, this software recorded and analyzed the whole process of tensile deformation. When compared with the results of the simulation analysis using ANSYS, this method achieved a relative error within ±0.75%, demonstrating the reliability, feasibility, and advantage of this method and its corresponding applied software and hardware.