A sterilized connection apparatus 4 includes a sealing unit 9 which forms a decontamination space S1 between an isolator 2 provided with a first cover body 11 and an incubator 3 provided with a second cover body 21, a decontamination medium supplying unit 10 which supplies a decontamination medium to the decontamination space S1 via a supply pipe line 41, and a discharge pipe line 43 which discharges the decontamination medium of the decontamination space S1.Since the decontamination space is formed as a circular decontamination space of a small capacity surrounding the cover bodies, decontamination can be efficiently performed.