中文摘要：

加入WTO后,我国粮食市场更加开放,国内粮食市场与世界粮食市场的联系更加紧密。先从粮食整体角度,利用VAR模型研究我国粮食进出口贸易是否存在＂大国效应＂,接着利用协整模型研究我国粮食分品种进出口贸易是否存在＂大国效应＂。结果显示：从粮食整体来看,我国粮食进口存在＂大国效应＂,但我国粮食出口并不存在＂大国效应＂;从粮食分品种来看,玉米以及大豆的进口存在＂大国效应＂,而我国大米进口不存在＂大国效应＂,但是大米出口却存在一定的＂大国效应＂。我国是玉米出口大国,玉米出口却不存在＂大国效应＂。最后给出相关政策建议。

英文摘要：

After joining the WTO,China＇s grain market has grown more open and drawn closer to the world market.The paper,by using the VAR model,studies the relationship between China＇s grain trade and international grain prices.Meanwhile,cointegration analysis is used to explore the relationship between sub-species of grain import-export trade and international grain prices in order to study whether＂big country effect＂exists in China＇s grain import-export trade. The VAR model results show that this effect does exist in China＇s grain import while it does not in China＇s grain export.Cointegration analysis shows that the effect exists in corn and soybean imports and rice exports,but not in rice imports. Although China is a major corn exporter,＂big country effect＂is not found in corn exports.Finally the paper puts forward some suggestions.