This paper analyzes the problems existing in indicator measuring of floor area ratio in current regulatory detailed planning and their reasons, and taking the economic analysis on the relation among floor area ratio, land price and land development profit as the entry point, probes into how to measure the indicators of floor area ratio.

But accompanying with the developing of modern civilization,there are also many problems such as the lack of land,traffic jam and city pollution etc,and the lowness of land utilization ratio is pretty grave.

The classification system of land use cannot fully reflect social and economic attributes in mid-sized and microcosmic regional land use,making the evaluation function of land use ratio inaccurate.

The reasons caused the low land use rate and large land use in residence construction in village and small town are analyzed; at the same time some effective measures are elaborated for land saving and enhancing land use rate.

The development of the concept of land use rate, and its advantage and disadvantage under the new situation were analyzed.

This paper applies the C2R model of DEA to evaluate the land use efficiency of 29 cities in Hunan Province, with the result that the urban land use efficiency is high in the province as a whole, and that it is higher in the east than in the west.

Based on the summary of the research results in evaluating land use efficiency,the paper presents a basic idea for the construction of the evaluation system of land use efficiency.

This paper concludes the main historical events affacting the variation of land use efficiency since the foundation of the People s Republic of China.