Rural-urban conversion efficiency is an indicator used to measure economic development level andreflects the efficiency of utilizing cultivated land resources in the economic development.The rural-urbanconversion efficiency of China in 1999-2008is calculated using the method of data envelopment analysis(DEA).Results indicate that the rural-urban conversion efficiencies of 31provinces(districts)changed a little in 1999-2008

basically being between 0.7and 0.8.The rural-urban conversion efficiency and scale efficiency had the same change trend

which further shows that the change of the rural-urban conversion efficiency was mainly induced by scale efficiency.The number of provinces(districts)whose pure technical efficiency is efficient was higher than the number of provinces whose conversion efficacy and scale efficiency areefficient.However

the number of provinces with the optimal pure technical efficiency tended to decrease.The phenomena of over rural-urban conversion and low land use efficiency existed in all the provinces in allthe years.It can be concluded that the rural-urban conversion efficiency can be raised by adjusting investmentamount

investment structure and output quantity.