In order to explore main causes and dynamic mechanisms, the latest data of past sequences of solar radiation and volcanic dust are adopted in this paper to simulate the climate change during the Little Ice Age.The results show that the annual mean temperature decreases in Eurasia.The decreases in temperature vary with regions and seasons.The amplitude of decrease in temperature in high latitude is bigger than that in low latitude, and it is higher in winter than in summer.The decrease of annual mean temperature is from 0.2℃ to 0.4℃ in the region to the north of the Yangtze River.Climate in different monsoon region has different response to the changes of solar radiation and volcanic dust.The precipitation is decreased obviously in eastern and southern China, which is controlled by southeastern monsoon climate at present.The annual mean decrease is about 0.5 to 1.5 mm/d.While the precipitation slightly increases or remains almost unchanged in the vast areas which are controlled by westerlies and southwestern monsoon.The maximum annual mean increase is less than 0.5 mm/d.These results are mainly consistent with the historical evidences and natural records.