A scanning imaging system for security inspection of an object, characterized by comprising: a conveying unit configured for bringing the object to move along a conveying direction of the conveying unit; a plurality of radiographic sources at one side of the conveying unit, the plurality of radiographic sources being arranged successively in a direction vertical to a plane, in which the conveying unit is located, and configured for alternately emitting ray beams to form a scanning area; a linear detector array at the other side of the conveying unit, the linear detector array being configured for detecting first projection images, which are formed after the ray beams emitted by the plurality of radiographic sources penetrate through the object, in the process of the object passing through the scanning area; and an imaging unit configured for obtaining a first reconstructed image of the object based on the first projection images of the plurality of radiographic sources, wherein the linear detector array comprises a plurality of linear-array detectors arranged successively along the conveying direction of the conveying unit, the plurality of linear-array detectors being configured for detecting the first projection images, which are formed after the ray beams emitted by the plurality of radiographic sources penetrate through the object, in the process of the object passing through the scanning area, respectively, and charaterized in that the plurality of linear-array detectors are arranged centripetally around a vertical line, on which the plurality of radiographic sources are located, and each linear-array detector is arranged to deflect towards the vertical line, on which the radiographic sources are located. a conveying unit configured for bringing the object to move along a conveying direction of the conveying unit; a plurality of radiographic sources at one side of the conveying unit, the plurality of radiographic sources being arranged successively in a direction vertical to a plane, in which the conveying unit is located, and configured for alternately emitting ray beams to form a scanning area; a linear detector array at the other side of the conveying unit, the linear detector array being configured for detecting first projection images, which are formed after the ray beams emitted by the plurality of radiographic sources penetrate through the object, in the process of the object passing through the scanning area; and an imaging unit configured for obtaining a first reconstructed image of the object based on the first projection images of the plurality of radiographic sources, wherein the linear detector array comprises a plurality of linear-array detectors arranged successively along the conveying direction of the conveying unit, the plurality of linear-array detectors being configured for detecting the first projection images, which are formed after the ray beams emitted by the plurality of radiographic sources penetrate through the object, in the process of the object passing through the scanning area, respectively, and charaterized in that the plurality of linear-array detectors are arranged centripetally around a vertical line, on which the plurality of radiographic sources are located, and each linear-array detector is arranged to deflect towards the vertical line, on which the radiographic sources are located.