Republic of Korea has been applying offset to defense acquisition program for some benefits such as modernization of defense industry and enhancement of R&D capabilities since 1983. But in point of implementation, there is the possibility of delay of offset agreements based on the value of proposed technologies. As it often happens that the delay of offset agreement negatively affects the time schedule of main defense deal, it is necessary to prepare for this issue. The purpose of this study is to extract some factors affecting the duration of offset agreement by statistical analysis. Reviewing existing papers and contract process, nationality of enterprise, the number of project participants, properties of project, the number of technologies in the first proposal, level of domestic defense technology in each weapons system, the amount of main contract were used as independent variable and duration of agreement as dependent variable. To hypothesis testing, correlation and multiple regression analysis were conducted using the previous 25 contract cases. As a result of correlation analysis, the amount of main contract, the number of technologies in the first proposal and properties of project have positive relationships with dependent variable. In multiple regression, the amount of main contract and the number of project participants have significant effect on the duration of offset agreement.