The present disclosure relates to multi-modality detection systems and methods. One illustrative multi-modality detection system may include a distributed radiation source configured to irradiate an object under detection, a primary collimator configured to separate rays of the distributed radiation source into two parts, wherein one part is for CT detection and the other part is for XRD detection, a CT detection device configured to perform a CT detection to acquire a CT image of the object under detection, and an XRD detection device configured to perform an XRD detection to acquire an XRD image of the object under detection, wherein the CT detection and the XRD detection are performed simultaneously.