The total dynamic changes of the cultivated land from 1988 to 2007 in Changchun City of Jinlin Province, China, were analyzed using the statistic data and the detailed inquisitional land materials and investigated alternated land information.On the basis of this, the main driving factors of the cultivated land amount changing were calculated using the principle component analysis.Ten correlated factors which influence the total quantity of cultivated land changing, such as total population, GDP, the investment of social fixed assets and the tertiary industrial output, etc.were also calculated at the mean time.The results shows that:from 1988 to 2007, the total amount of the cultivated land of Changchun decreased, and the economic development was the main driving factor of the amount of cultivated land in Changchun.In the principle analysis, the factors of the correlation matrix, such as the characteristic value, contribute ratio of principle component and the accumulated contribute ratio, correlated highly and inevitably.Most of the factor loadings are bigger than 0.9 except that of forestry, animal husbandry and fishery, which count for 0.575 out of the total output.Proportionality factor loads of the yield rates of the cultivated land, forestry and fishery are relatively high in the total output.It can be concluded that the main driving factors of the dynamic change of land cultivation amount are socio-economic development, population increasing and the progress of the agricultural techniques.