Recently the Korean government announced that minimum wage policy would be applied even to apartment security staffs by 2015 who had been waived from the policy enforcement for their unique work conditions. This caused apartment management to introduce unmanned security system instead of employing security staffs because of fearing possible hike of management fees. People recklessly tend to believe unmaned system is cheaper than maned system if minimum wage guideline is applied. This study examines the economic feasibility of two different apartment security systems by utilizing cost-benefit analysis: maned and unmaned security systems. The authors estimate the costs and the benefits of each security system for 5 years(2014-2018) with application of social discount rate(5.5%). Thirty six apartment complexes at 8 different areas(meons and dongs) in Asan, Chungcheongnam-do province were surveyed. And to attain the exact costs of unmaned system establishment and operation, the authors interviewed persons working for the unmaned security corporations. The benefit-cost(B/C) ratio for unmanned security system is 1.66% at minimum and 1.30% at maximum. while B/C ratio for manned security system is 1.42% and 1.66% respectively. This results mean that people's belief is not correct, that is, transferring from maned system to unmaned is not always economically efficient. Benefits of maned security system is more diverse than unmaned system. The former provides living conveniences(parking helps and keeping parcels) and social benefits(employing aged worker and giving them opportunities to enjoy happier lives) as well as security benefits like crime prevention. The latter provides security benefits only, but that effect is also doubtable. Taking into account these diverse benefits maned system provides, the B/C ratio of maned system is equitable or higher than unmaned system.