Abstract: Development status of engineering analysis software of block theory is sketched out. Based on the new findings, calculation codes by different program languages under DOS are translated and integrated into Windows software by means of Visual Basic language, OpenGL and API technologies. Preliminarily developed software includes the necessary functions in engineering analyses such as stereograph projection, unlocated and located block analysis, block figure analysis (including concave block), block stability analysis, reinforcement measures suggestion, and figure analyses of maximum key block and stochastic block in tunnel and slope. The software can input data by person-machine interface or data file, analysis results can be displayed graphically, the graphs can be zoomed in and out, moved and animated and the software possesses interfaces with AutoCAD and PostScript. All these advantages can make the software be operated easily and comfortably. The software at present has been applied in some rock engineerings.