Based on mandarin yield data from 1971-2008,the meteorological yield of mandarin was calculated by use of smooth average methed and furthermore the climatic harvest patterns were classified into high-yielding year,mean-yielding year,and low-yielding years,By using the field observation data from 2001 to 2008,the mean growth period,and the relationship between daily mean temperature,daily maximum temperature,daily minimum temperature and growth of mandarin was analyzed,and the temperature indexes of growth period of mandarin were determined,which include the upper limit of optimum temperatures,extreme value of lower limit lowest temperatures,the harmful temperature,the death temperatures of the development period from sowing to maturation of mandarin.on this basis,the Cumulative index of low-temperature impact was designed, the Cumulative index ranges of low-temperature impact of each season were established, Design and development of the citrus low-temperature analysis of disaster early warning system ,Low-temperature dynamic monitoring and early warning of disasters was conducted.