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Using the data of daily temperature, corn development phases, and corn chilling damage during the growing periods from 1961 to 2003 from 69 counties over Heilongjiang Province, based on the principles of the accumulated temperature theory, established and analyzed are the index system, risk degree, and forecast model of chilling damage occurrence of corn during different development periods. The trends of corn chilling injury risks during the 43 years are analyzed and tested with the MannKendall method. The results show that the period of 1961 to 1983 is a highrisk period of lowtemperature/chilling risk with the highest risk years in 1964, 1969, 1972, and 1983; 1983 to 2003 is the lowrisk period, especially obviously increased relative accumulated temperature (lowrisk period) being found in the later years. The risk forecast model of corn chilling damage can forecast and assess the risk and area of chilling damage. The outcome verification indicates that the model has good objectivity and usability.