This study examined the Democratic People’s Republic of Korea (DPRK)’s illegal trade in UNsanctioned items as revealed in the UN panel of experts report in order to estimate the types of illegal trade in nuclear items, one of the UN-sanctioned prohibited items, and to find efficient ways to block it. Also, The research revealed that DPRK secretly imports UN-sanctioned prohibited items without going through customs through maritime transshipment, conceals or disguises them through identity laundering by falsifying documents at customs clearance, and makes various attempts to escape the international community’s surveillance, such as using a combination of methods such as Re-Flagged and Double-Flagged for identity laundering, and concealing them without operating the Automatic Identification System (AIS) at sea. The DPRK’s Illicit trade cases have been divided into two types of transactions: those that violate customs clearance procedures by providing false information to customs through disguise or concealment, and those that do not go through normal customs procedures, such as smuggling. To block customs violations, technical measures such as increasing the number of inspections of container ships or improving the accuracy of inspections are required, while to block smuggling, since it does not go through physical inspections, there are ways to monitor it through satellite images or strengthen border enforcement such as airport bays and land routes. As a result, DPRK’s nuclear items are designated as sanctioned items under UN resolutions, and it is assumed that DPRK and its networks will attempt to trade illegally through a combination of customs clearance violations and non-customs clearance violations, depending on the circumstances. Furthermore, since DPRK is subject to extensive sanctions from the international community, including the UN, in connection with its nuclear weapons program, illegal trade continues, and efforts should be made to block illegal trade through physical inspection at customs clearance.