Since 2015, Korea Institute of Nuclear Nonproliferation and Control (KINAC) which is technical support organization of Nuclear Safety and Security Commission (NSSC) has introduced and implemented annual national inspections of nuclear facilities including power reactor, fuel manufacturing facility, research institute, and nuclear material use companies for State’s System of Accounting for and Control of Nuclear Material (SSAC). The national inspection consists of 6 inspection items as follows. Organization and job, record and report, measurement system, procedure of import/export and accounting of specific nuclear material, education and training, other matters related to accounting. The national inspection is usually conducted for 2 weeks and consists of document inspection, on-site inspection, and interview with a person in charge. As a result of the inspection, the authority can issue a legal corrective order to the operator. In this paper, based on the national inspection results for 7 years, inspection trends that focus on corrective order were analyzed. The main factors influencing the inspection results were the inspector's propensity and the points pointed out by other facilities. Based on the analysis results, we proposed improvement points for future national inspections.