ACT inspection system, comprising: a scanning device, being provided with an X-ray machine or an accelerator and a detection device, and being configured to rotate at a non-uniform speed in at least partial process of scanning an object to be detected (a); an imaging device; and a rotation monitoring device, being configured to detect a rotating angle of the scanning device and send a high level signal to the imaging device each time the detection device rotates by a preset angle; wherein the imaging device is configured to determine data of the detection device bound with high level signals sent by the rotation monitoring device as effective detection data, and generate a CT image based on the effective detection data; wherein, the imaging device comprises a data collecting and selecting device and an image processing device, the data collecting and selecting device is configured to acquire the effective detection data and transmit the effective detection data to the image processing device, and the image processing device is configured to generate a CT image based on the effective detection data transmitted by the data collecting and selecting device; and the data collecting and selecting device comprises a data acquisition device and an image collection device, the data acquisition device is configured to acquire all the data of the detection device, and the image collection device is configured to select the effective detection data from all the data of the detection device acquired by the data acquisition device and transmit the effective detection data to the image processing device, characterized in that, the scanning device is adapted to scan the object to be detected while swinging in a reciprocating manner. a scanning device, being provided with an X-ray machine or an accelerator and a detection device, and being configured to rotate at a non-uniform speed in at least partial process of scanning an object to be detected (a); an imaging device; and a rotation monitoring device, being configured to detect a rotating angle of the scanning device and send a high level signal to the imaging device each time the detection device rotates by a preset angle; wherein the imaging device is configured to determine data of the detection device bound with high level signals sent by the rotation monitoring device as effective detection data, and generate a CT image based on the effective detection data; wherein, the imaging device comprises a data collecting and selecting device and an image processing device, the data collecting and selecting device is configured to acquire the effective detection data and transmit the effective detection data to the image processing device, and the image processing device is configured to generate a CT image based on the effective detection data transmitted by the data collecting and selecting device; and the data collecting and selecting device comprises a data acquisition device and an image collection device, the data acquisition device is configured to acquire all the data of the detection device, and the image collection device is configured to select the effective detection data from all the data of the detection device acquired by the data acquisition device and transmit the effective detection data to the image processing device, characterized in that, the scanning device is adapted to scan the object to be detected while swinging in a reciprocating manner.