In order to discuss the dynamic changes of rural labor force in Heilongjiang province from 1990 to 2011, the rural employment, rural labor force, regional GDP, rural residents’ consumption, rural fixed asset investment and the per capita net incomes of rural residents were selected as research objects, of which the rural employment was regarded as an explanatory variable. The elasticity coefficients of the macro factors were obtained by the establishment of state space model and the following estimations of Kalman filtering. The analytical results suggest that among all factors the rural labor force is the main factor that positively affects the rural employment over the long term, while the rest of the four factors are in the course of fluctuations between positive and negative correlations. In addition, the rural employment was significantly influenced by each macro factor involved in the study before 1998 and then remained stable.