Lead halide perovskite CsPbX3(X=Cl，Br，I) semiconductor nanocrystals have excellent photoelectric properties，such as narrow full width at half maximum，tunable emission wavelength and high photoluminescence quantum yield,which have great potentials for their applications in light-emitting diodes，lasers,solar cells．By introducing impurity atoms，the optoelectronic properties of perovskite nanocrystals，including the width of band gap，the intensity of photoluminescence and quantum yield can be adjusted and the stability of perovskite nanocrystals can be improved．The type and concentration of impurity also affect the electron band structure and photoluminescence properties of perovskite nanocrystals．Therefore，the doping of perovskite nanocrystals has become the focus of research in recent years．The A/B/X sites of ABX3 nanocrystals can be replaced by impurity atoms．The B-site ions have a significant effect on the properties of nanocrystals．In this paper，we review the doping methods，mechanism，and effects on the structure and photoelectric properties of perovskite nanocrystals on B-site．The doped elements mainly include manganese，lanthanide，tin and alkaline earth metals．Doping these ions in perovskite nanocrystals can effectively improve the optical performance and stability of perovskite nanocrystals，and further promote the practical application．