This paper briefly introduces the concrete steps of EMD (Empirical Mode Decomposition) method, and applies EMD method into the multi-time scale analysis on fluctuation of cultivated land quantity and its driving force in China since 1949. We also reveal the fluctuation law in the amount of cultivated land quantity. At the same time, based on the fluctuation of different time scales, qualitative forecast on the fluctuation trend of cultivated land quantity in China in future is carried out in order to offer references for establishing prediction model of cultivated land quantity. Research result shows that downward trend of cultivated land quantity is inevitable in China in the future, showing a basic form of an exponential decline during a short period of time. However, situation will be improved with the implementing of a series of land-control policies and paying attention to the issue of rapid reduction of cultivated land. Thus, we put forward several suggestions: (1) Strengthen the research and control on the cultivated land quality in the overall land use planning; (2) strengthen the continuity and durability of land macro-control; (3) strengthen the protection responsibility of cultivated land for leadership at all levels.