Abstract: Based on ground surface temperature data of 80 meteorological stations and frost damage losses data of winter wheat from 1961 to 2010 in winter wheat planting area in Shanxi province，authors defined the frost processes with minimum ground surface temperature，and constructed the climatic index with frost process，and then analyzed the annual variation and spatial distribution of climatic index.The results showed that the possible frost years could be identified by relative accumulated frost.The mean value distribution of accumulated frost of mild frost damage，moderate frost damage，severe frost damage and all frost processes were similar.The mean value of accumulated frost was in sequence of severe frost damage>moderate frost damage>mild frost damage in same region.The climatic index for frost damage constructed by ground surface temperature was the research foundation of making real-time evaluation and risk zonation for frost damage.

Key words: Winter wheat, Frost damage, Accumulated frost, Climatic index