A darkroom type security inspection apparatus and a method of performing an inspection using the darkroom type security inspection apparatus. An apparatus includes a housing constituting a closed darkroom, and assemblies disposed inside the housing. The assemblies disposed inside the housing include: a sample collecting unit configured to collect a sample, a conveyor unit, and a X-ray detection unit to detect a position of the objected to be inspected, wherein the X-ray detection unit is configured to determine the position of the objected to be inspected within the sampling assembly so that the object to be inspected together with the conveyor unit is conveyed to an expected position; and a sample processing assembly, wherein the assemblies disposed inside the housing are communicated by fittings or connectors.