To overcome the limitations of traditional deformation measurement methods and complete the comprehensive measurements of the general deformation and the various point displacements within a measurement scope in any time, the Digital Speckle Correlation Method(DSCM) was used in accurate deformation measurement. Firstly, by comparison with traditional methods, it summarized the advantages of the method in noncontact, high precision, simple and flexible operation, overall measuring and so on. And then the principles of the DSCM were elaborated on the five aspects, the relevant mathematical models were established and the corresponding measurement and analysis software XJTUDIC was developed. By using this software with the relevant hardware devices, a tensile deformation process was tested and obtained results were compared with that of traditional measurement method using an extensometer. Obtained results indicate that the error is within 0.2%, which fully validates that the method and corresponding software and hardware are reliability and feasibility and it provides an effective and reliable tool for the precise and comprehensive deformation measurement.