Generally, non-destructive testing methods based on the fast neutron technology, such as the associated alpha particle detection technology, can detect hidden hazardous materials without affecting the detected object. The effective neutrons are labeled by recoil alpha particles produced in a D-T reaction, which can significantly improve the signal-to-noise ratio of neutron detection. Meanwhile, the spatial information of the detected object can be obtained based on the spatial resolution of alpha particles. Therefore, neutron detection methods based on accompanying alpha particles have important application prospects in the field of security inspection. The principle and system composition of the neutron detection method based on associated alpha particles are briefly introduced herein. Then, key components of the detection system, such as the neutron tube, alpha particle detector, and gamma detector, are described. Next, the associated alpha particle neutron detection system, which is being studied worldwide, and its progress are presented. Finally, the prospects of this detection method are discussed.