Abstract: The population dynamics and population quantity of Apodemus agrarius have been analyzed and predicted in Yuqing County Guizhou Province from 1987 to 2005. The results show that average annual capture rate is 6.90%±2.57%; there are two peaks in population development, first peak appears in May-June and second in October-November each year, the highest is in June; there are significant differences of stocks in different year，different months, and different seasons. The Apodemus agrarius population quantity graduation standard has been formulated. March stocks (X1) of established applications base, April stocks quantity × April reproductive index (X2) June stocks forecast peak volume density (Y) of two short-term forecast models are Y=1.3669X1+5.6175. Y=0.4988X2+7.2940, May forecast the number of degree and occurred degree two months or three months in advance, and after the reverse running and confirmation, the value and magnitude prediction data accord to the actual data, the value prediction average tallying rate is 86.61% and 86.11%, the magnitude prediction average tallying rate is 78.95%. The result is almost accurate, and therefore these prediction models have usability and the feasibility.