The present invention relates to a structure of a switchgear with an arc protection system including an arc optical sensor to detect an arc, a relay to determine an occurrence or non-occurrence of a fault current by receiving an arc signal detected by the arc optical sensor, and an arc eliminator to earth an arc-generated side bus bar in response to an operating signal with respect to the determined fault current, wherein the arc eliminator has a test position or a service position within the switchgear.