Abstract: Associated particle imaging (API) is an important means of performing explosive detection and active verification, and the position resolution and time resolution of the associated alpha particle detector directly determine the spatial resolution of the imaging system. Based on the neutron generator of the Key Laboratory of Nuclear Data in CIAE, the ZnO：Ga with fast time response was combined with the latest position sensitive photomultiplier tube (PSPMT) H13700 to design an associated alpha particle detector system for API. The 256-channel signal was simplified to 4-channel signal by SCDC-TCOG, which was collected and analyzed by the digitizer DT5730. The time resolution performance and position resolution performance of the associated particle detector were measured. The position resolution is better than 1 mm by the knife edge method, and which was verified by the slit method and the grid method. The time resolution of the system is better than 1 ns by the association measurement method, which can meet the application requirements.