In this study, attempts have been made to construct a standard cost specification structure fit for Korean Navy, and to estimate maintenance and operating costs of FFX, PKX-A, and PKX-B. The maintenance and operating costs of FFX along its whole life cycles, 30 years are estimated as 716.7 billion won via engineering analysis methods, while PKX-A, and PKX-B as 154.4billion won and 86.6 billion won, respectively. This study is expected to be able to provide meaningful decision making data for not only short and/or mid term operating planning but military budgeting.