Abstract: Cultivated land is an important material basis and the most basic means of production for human survival and social development. The rational development and utilization of cultivated land is very important for stabilizing food production, ensuring effective food supply, and promoting rural economic and social stability. This paper first estimates the cultivated land use efficiency of Yunnan and its 16 areas from 2009 to 2019 by using the data envelopment analysis method, then analyzes its temporal and spatial change characteristics, and finally studies the influencing factors of cultivated land use efficiency by using Tobit model. The results show that the comprehensive efficiency of cultivated land use in Yunnan was not at effective level and a downward trend from 2009 to 2019; the comprehensive efficiency of cultivated land use in Yunnan among them; the change of comprehensive efficiency and scale efficiency in a similar downward trend, while the change of pure technical efficiency being relatively small and effective in most years. The cultivated land use efficiency and its changing trend of 16 areas in Yunnan are different, which can be roughly divided into four types: stable effective state type, continuous increase to effective state type, continuous decline to ineffective state type and fluctuation type. The utilization efficiency of cultivated land in 8 areas had reached an effective level. Most of them were traditional agricultural main producing areas with good agricultural production conditions in Yunnan (except Nujiang Prefecture), and were also heavily influenced by various preferential policies of the state. Except Yuxi City, they were mainly distributed in the marginal areas of Yunnan. In terms of the spatial pattern change of cultivated land use efficiency, there were many areas with high value of cultivated land use efficiency in Yunnan in 2009,which were distributed contiguously, mainly in the east and west sides of Yunnan. By 2019,there were few high-value areas in the central region in Yunnan, and the high value area decreased, and the distribution area contracted to the marginal areas of Yunnan. From the perspective of the influencing factors of cultivated land use efficiency, per capita GDP agricultural development level, three main agricultural product output factors have positive effects on cultivated land use efficiency, while fertilizer input and rural per capita disposable income have negative effects on cultivated land use efficiency.

Key words: utilization efficiency of cultivated land, data envelopment analysis, Tobit model, influencing factor, Yunnan