In order to prove knowledge has become the most active driving force in China’s economic growth, a regression equation was used in this paper, according to TFP growth rate, based on Solow Growth Equation. By introducing the data of real GDP, labor input and capital input, all data over the period 1979-2005, the capital-output elasticity, labor-output elasticity in this test were got. Using capital-output elasticity and labor-output elasticity, then the economic contribution rate of labor, capital and knowledge were got. Through data analysis, it was determined that knowledge has a great impact on economic growth. Because China’s economic contribution rate of knowledge is far lower than the average level of developed countries, the expenditure on R&D and personnel training should be raised, while we should strive to expand space of policy innovation.