In this paper,based on the material flux analysis model (MFA) and its" corresponding theories and algorithms of "virtual land",virtual land contents of five primary agricultural products are calculated and "virtual land trade" hidden in those imported and exported products are also obtained through analyzing the primary agricultural product trade between China and ASEAN.In the process of calculation,following the thought of changing agricultural products to "virtual land trade ";land content,trade condition and spatial distribution of agricultural products were integratedly considered.The results indicate that China exported 73,057 kin:of virtual land area to ASEAN by tea,vegetables,maize and grain,while ASEAN exported 57,332 km2 to China by natural rubber from 2002 to 2005.It is obvious that China has lost 15,725 km2 arable land through agricultural product trade.Additionally,in order to describe the specific process of calculation on virtual land trade,Thailand was taken as an example to analyze its international trade of rice and wheat from 1991 to 2005 and calculate their "virtual land trade" 2001 through 2005.According to the analysis and calculation,it is not difficult to conclude that "virtual land trade" is very important and could be used for China to guide agricultural export or import structure and maintain sustainable use of land resources.