Since 2017, the Korea Institute of Nuclear Nonproliferation and Control (KINAC) has been implementing State System of Accounting for and Control of Nuclear Materials (SSAC) training courses for the nuclear Newcomer States. This IAEA SSAC course for Newcomer States aims to provide overall concepts and techniques, particularly on nuclear material accountancy and control systems, and address future challenges with regard to developing new nuclear power plants. Due to the restricted travels and limited in-person access to training and facilities from the COVID-19 pandemic, however, a new software was developed to substitute a technical tour on bulk handling facility (BHF) of the training course, and the course was favorably shifted to online in 2021. This newly built training software allows participants to follow each step of the technical process at a virtual bulk handing facility, and provides a video tour for such conditions where the software is found difficult to operate. Another feature of the development is a security function that prevents access of unauthorized users to the software. The achievement is expected to strengthen the SSAC of Newcomer States and ensure the practical implementation of safeguards from the initial stage of their novel nuclear power program through cooperation with IAEA. This contribution of the Republic of Korea (ROK) as one of the leading countries in the field of nuclear nonproliferation will further extend the partnership between IAEA and ROK and promote cooperation with the Newcomer States.