Korea has signed nuclear cooperation agreements (NCA) with 29 countries. Nuclear materials, materials, equipment, and technology transferred under the agreements are “internationally controlled materials (ICM)” under the Nuclear Safety Act. The main obligations imposed on those items include ensuring peaceful use, safeguards, physical protection, annual inventory reporting, and retransfer with supplier prior consent. The Nuclear Export and Import Control System (NEPS) handles the export control procedures for transferring ICM. After import, inventory management for ICM in Korea would be transitioning to an item-based system through the Obligation Tracking System for internationally controlled item (OTS) currently under development. A one-stop import and export control system for ICM can be established when information is well-linked between these two systems. This paper aims to derive a methodology for integrating NEPS and OTS. NEPS-OTS coupling begins at the receipt confirmation and shipment notification stages in NEPS. When importing ICM under NCA, the inventory change (code RF: receipt foreign) is entered in OTS by getting the information that has completed the receipt confirmation in NEPS. Conversely, during export, the information that has completed the shipment notification procedure in NEPS is linked to the OTS so that the entire cycle from import to re-export of the ICM can be concluded. Inventory verification for retransfer, checking that the book inventory remains positive value, is impossible under the current system. This issue can be resolved by enabling inventory information in OTS to be displayed in NEPS. Determining when and how to generate the obligation code for imported ICM is essential for NEPS-OTS coupling. Manual input may be necessary for some cases with multiple obligations. Nevertheless, it is more efficient from a system communication protocol to automatically generate and impose a single obligation based on the supplier country information in NEPS. Moreover, it is important to automatically link crucial information available in NEPS to reduce the administrative burden on OTS users and discrepancies between systems. Most required OTS data, such as country obligation, item categories, quantity, physical or chemical form, and receipt date, can be directly linked from NEPS. However, NEPS improvement is needed for digitizing the receiver information and facility data, like the material balance area. The NEPS-OTS integration involves sharing data as a system and encompasses the connection between export control and inventory management. Future work to link some information in NEPS -OTS with the KSIS could be suggested to enhance efficiency and effectiveness in managing ICM.