Integrated Terrain Unit Map (ITUM) with several overlays of land elements is being developed in the world. The ITUM is a new computer mapping system. The project of Tengchong, land resource evaluation, was supported by software-ARC/INFO. After ITUM was digitized, it was used as base for land resource evaluation in Tengchong.Two models for evaluation, TT = VI* (V2 + V3 + V4)/3* 0.01 and TT2 = V1*V2*V3*V4* 0.000001, were designed. It was borne out that the first model was better than the second one by comparing output maps of evaluation with land-use map of Tengchong.By use of statistic analysis for data, four classes of land were divided:Class 1, Lands in class 1 have few limitations that restrict their use.Class 2, Lands in class 2 have some limitations that reduce the choice of plants or requiremoderate conservation practices.Class 3, Lands in class 3 have severe limitations that reduce the choice of plants or require special conservation practices.Class 4, Lands in class 4 have severe limitations that make them generally unsuited to cultivate.Area of 541.91 sq. km is suitable to farm in Tengchong. It is onely 29.52 per cent of whole area. But now, area of 534.94 sq. km has been cultivated and a few arable virgin in Tengchong can be cultivated.