The potential of roadmapping systems in updating, maintaining and sharing technology roadmaps has been argued in many articles but the systems have not been dealt with as a research topic. Therefore, this research purposes to develop an online roadmapping system, which is called an e-TRM system, to improve the efficiency of roadmapping at the national level in Korea. For the purpose, the roadmapping process for national R&D planning and its main activities were analyzed, based on which system requirements and main functions were identified. After the functions were successfully implemented in the TRM system, the system was applied to the 2009 national roadmapping process to verify its feasibility and utility. The system will enable to digitalize R&D planning in Korea and share the planning results nationwide. Also, the research results are expected to provide useful guidelines for those who are in charge of developing TRM systems.