Scintillators are widely used for x-ray detection in various fields, such as medical diagnostics, industrial inspection and homeland security. Nanocrystals (NCs) of metal halide perovskites (MHPs) and their analogues showed great advantages as x-ray scintillators due to their cheap manufacturing, fast decay time, and room temperature scintillation from quantum confinement effect. However, there are still many challenges unsolved for further industrialization. Herein, it is necessary to summarize the progress of scintillators based on NCs of MHPs and their analogues. In the first section, the scintillation mechanism and key parameters are outlined. Then, various NCs of MHPs and their analogues used as scintillators are reviewed. Finally, the challenges and outlook are discussed. It is believed that NCs of MHPs and their analogues are favorable for large-area and flexible x-ray detectors.