High-energy radiation detection and imaging technology has important applications in high-energy physics research, medical imaging, industrial detection, and other fields. Lead-free metal halides have many advantages, such as low toxicity, good stability, high light yield, and large stokes shift; they exhibit excellent potential in indirect X-ray detection. The latest research progress of lead-free metal halide scintillators and imaging devices is reviewed herein. First, the material composition and luminescence mechanism are introduced. The key parameters of scintillator performance are listed. The synthesis methods of single crystal, powder, and nanocrystal are summarized. Some recent novel ideas about improving the resolution of imaging devices are also described. We focus on the new-type scintillator imaging devices, including composite film, ceramic, glass, and structured scintillators. Finally, we have summarized the challenges and potential problems of scintillator imaging detectors and provided some suggestions.