The invention relates to an object detection method, and especially relates to a hazardous article detection apparatus, a detection method, and an application thereof. A passive THz hazardous articledetection apparatus includes a visible light image sensor, a THz imaging sensor, a processor, an image memory, an operation table and a displayer, wherein the processor is respectively connected to the visible light image sensor, the THz imaging sensor, the image memory and the displayer. In the invention, a problem that hidden hazardous articles, carried by people, cannot be quickly and accurately detected in the prior art is solved, so that the apparatus and method has important significance for fighting against high-dangerous behaviors, such as violence and terrorism, revenge on society, etc. The apparatus, if successfully applied, can make criminal offenders frightened in mind and can reduce generation of such cases fundamentally.