Abstract: This paper explores the correlation between the dynamic change of cultivated land area and social and economic development in Tibet, according to the statistical data of Tibet from 1978 to 2017, to calculate the changing situation of cultivated land area. At the same time, twelve socio-economic development factors are chosen scientifically, and principal component analysis and regression analysis are integratedly used to analyze the quantity changes of cultivated land and driving foreces orderly. The research shows that: (1) The total area of cultivated land showed a trend of dynamical increasing, totally, the cultivated land area had been increasing 388.46 hm² per year from 227 600 hm² in 1978 to 242 750 hm² in 2017, average cultivated land area reduced from 0.13 hm² per capita in 1978 to 0.07 hm² per capita in 2017. (2) The driving factors of cultivated land changing be summarized as the economic, population, agricultural science & technology and industrial factor, the comprehensive score of cultivated land changing increased from −0.9 in 1978 to 1.7 in 2017. (3) The main driver forces of cultivated land changes are total investment in fixed assets, financial revenue, per capita net income of rural residents and gross domestic product, there was a positive correlation between the driver forces and the change of cultivated land area; the total area of cultivated land showed a trend of dynamical increasing in Tibet during 1978 to 2017, the rapid economic development has an obvious influence on the change of cultivated land area.