Paprika are a important agricultural exports in Korea. Unfortunately, paprika are not suitable for long-distance exports as they do not store well. One major cause of damage to fresh agricultural produce including paprika is infection with pathogenic microorganisms that cause post-harvest diseases during storage and distribution. To address this problem, research is underway to develop a range of surface sterilization techniques. The recent confirmation of the sterilization effects of reactive oxygen species(ROS) generated from plasma discharge has attracted substantial research interest in applying the plasma technology to agriculture. As such, this study develops a plasma sterilization system with the aim of improving storability of paprika. This system consists of an atmospheric-pressure plasma generator, a plasma controller, and a chamber for plasma treatment. The sterilization effect of the present system was examined using Erwinia carotovora that causes bacterial soft rot in paprika. The E. carotovora samples were treated with plasma for 30 and 60 seconds, respectively, at the plasma power 500W, 700W, and 1,000W. It was found that the samples treated for 60 seconds showed a 100% sterilization effect. Then, to validate the effectiveness of the system in maintaining the freshness of paprika, paprika were treated at the plasma power 1,000W for 30 and 60 seconds, respectively. As a result, browning was observed in the stem end of untreated paprika due to withering, whereas this phenomenon was delayed for 26 days in the stem end of plasma-treated paprika.