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Various indexes of crop cold damage are introduced and compared on the basis of published research findings at home and abroad, and the advantages and disadvantages are analyzed. The progresses in the researches on relative cold damage risk assessment at home and abroad are introduced. The analysis shows that the researches on crop cold damage abroad are mainly concentrated on the mechanisms of crop cold damage, but the studies on cold damage index, as well as the monitoring, prediction, risk assessment of chilling damage, are comparatively less. Further research in future is necessary. The researches about damage risk assessment are mainly based on the probability of cold damage and temperature variance coefficient, so to establish a comprehensive risk index in China. The research findings in the risk assessment combined with crop production loss have not yet been reported.