A security inspection system of persons comprises: a passageway (110) which provides an inspection space isolated from an ambient environment, one sub-passageway allowing persons (102) to be inspected to pass is provided in the inspection space, and each of the sub-passageways is provided with at least one millimeter wave imaging device (120) for millimeter wave imaging of persons (102) being inspected; and an ion mobility spectrometer (130) for ionizing particles of substance or gases that are given off or volatilized from the inspected persons (102) into the air in the passageway (110) and then measuring a mobility rate thereof under the action of the electric field to effect identification of substances. At least one radioactive substance inspection means (190) is provided in the passageway to detect whether the person being inspected carries radioactive substances.
