Abstract: Characterization of crystal structures is one of the routine tasks of transmission electron microscope (TEM). This paper introduces the relationship between any single crystal structure and a diffraction pattern of transmission electron diffraction. In order to further simplify the device operating and the analysis of transmission electron diffraction, the device operating system for intelligent acquisition of single crystal transmission diffraction data and diffraction data analysis program are proposed and designed with Python computer language according to the above relationship between a single crystal structure and a diffraction pattern of transmission electron diffraction. The main functions of the analysis software program are introduced. The software can give out the crystal structure, crystal cell parameters and diffraction crystal plane index according to the input real TEM diffraction spots pattern. On the other hand, the diffraction pattern characteristics of a crystal with a certain orientation will be calculated and analyzed with the software program. For example, the single crystal diffraction patterns of cubic, tetragonal, orthorhombic, hexagonal, and rhombohedral crystal systems with the basic crystal zone axis are calculated and summarized. It provides a reference or a useful tool for material researchers to characterize single crystal structures.