In order to provide a plasma sterilization apparatus with high plasma generation efficiency, the apparatus includes first and second electrodes (3, 2), a first dielectric body layer (1), and an insulating spacer (6). The first dielectric body layer (1) is disposed between the first and second electrodes (3, 2). The insulating spacer (6) is disposed between the first electrode (3) and the first dielectric body layer (1). The insulating spacer (6) has a lower permittivity than a permittivity of the first dielectric body layer (1).