The purpose of this paper is to take a look the effect of the physical security level of companies possessing national core technology on security performance and work efficiency. To this end, a survey was set out for about 200 security officers for a month. In the survey, the independent variable was physical security level, the parameter was security performance, and the dependent variable was work efficiency. Reliability analysis, validity analysis, discriminant validity analysis, etc. were analyzed for causality through SPSS. As a result, “Physical Security Level ⇒ Security Performance, Security Performance ⇒ Work Efficiency” was adopted, but “Physical Security Level ⇒ Work Efficiency” was rejected. Therefore, it was found that the physical security level affects work efficiency through security performance, which is a parameter. However, it was found that the physical security level did not directly affect work efficiency. In order to improve work efficiency in the future, improving security performance should be a priority.