Digital holography has a wide range of applications in displaying the surface morphology of three-dimensional objects. There have been many studies on the physical methods and implementation methods of digital holography. One of the main problems at present is to design a stable and fast reconfiguration software. This paper analyzes the basic principle of convolution based off-axis digital holographic reconstruction, and presents the process of 3D reconstruction of off-axis digital holography. The 3D reconstruction software of digital holography is designed and developed according to the basic principle and the process of reconstruction, and the parallel operation of 3D reconstruction is realized by OpenMP. Results show that the software can help researchers conveniently realize digital holographic three-dimensional reconstruction. The reconstructed parameters can be adjusted according to the requirements, and the spectra, intensity maps, phase maps and other information required in the reconstruction process can be obtained. The software meets the needs of digital three-dimensional reconstruction.