With the development of the global hydrogen energy industry, the importance of developing numerical simulation technology for hydrogen pipelines has significantly increased. At present, the simulation of gas transmission pipelines relies heavily on foreign commercial software, which limits software autonomy. Furthermore, most of the existing commercial simulation software is based on the C/S architecture, which places high demands on on-site equipment, involves complex operations, and performs poorly in simulating hydrogen and hydrogen-blended natural gas. To address these issues, this study designs and develops a steady-state simulation software for hydrogen transmission pipeline networks based on the B/S architecture. This software adopts the thermophysical property correction model for pure hydrogen and hydrogen-blended natural gas, integrating modern network technologies with high-performance numerical algorithms. Its objective is to provide higher-precision simulation data to support the stable operation of hydrogen transmission pipeline networks. In terms of functionality, the software supports independent thermophysical property calculation and complex pipeline steady-state simulations. It also provides a user-friendly graphical interface with flexible data interaction and export capabilities. These features greatly enhance the numerical simulation capabilities of hydrogen pipeline networks, thereby providing crucial technical support for the development of hydrogen pipeline transportation technology and contributing to national energy security.