This paper uses the change of the gap of urban-rural investment in fixed assets as perspective , uses annual statistical data during 1980 to 2010 to study on the relationship between economy growth and the change of the gap of urban-rural investment in fixed assets, by cointegration analysis and Granger causality test, comes to the conclusion that economy growth is one of the causes of the change of the gap of urban-rural investment in fixed assets whether the term is long or short, but the change of the gap of urban-rural investment in fixed assets affects economy growth only in the short term. Based on this, the paper puts forward that can be the starting point of regulation and control policy to make the deflected gap of urban-rural investment in fixed assets to realize reasonable regression through the economy growth and to promote economy quick growth through the reasonable gap of urban-rural investment in fixed assets.