Based on the material of climate and Matsucoccus matsumurae dispersal,according to the dispersal areas and the climate characteristics of the place infested, the effect was analyzed about the main meteorological factors to Matsucoccus matsumurae dispersal in the northeastern China. The results showed that : the mean-minimum-temperature of every ten-day and month of January presented the increasing trend (r = 0.86, P<0.05). The extreme-minimum-temperature in winter increased(r = 0.93,P<0.01) slowly,too. The changes in temperature of the years had something to do with Matsucoccus matsumurae dispersal in the northeast of China. The more rapidly was Matsucoccus matsumurae dispersed,the higher had the pest population density and had the more serious extent of injury when the mean-minimum-temperature and the extreme-minimum-temperature in January were increased evidently in the 1970s and the 1990s of last century. Therefore there was a significant correlation between the minimum-temperature and Matsucoccus matsumurae dispersal. The higher the ten-year of the mean-minimum-temperature was,the faster Matsucoccus matsumurae dispersal was. The lower the minimum-temperature was,the slower its dispersal was. The great range of dispersal and outbreaking of Matsucoccus matsumurae took place in the years of high minimum-temperature in January. The minimum-temperature in January and the extreme-minimum-temperature in winter increasing were the main factors of Matsucoccus matsumurae dispersal. There was no relation between dispersal and variation of precipitation after conscious,air relative humidity and the maximum summer temperature.