Based on Landsat TM data in 1990, 2000 and 2007, using the normalized bare index, unsupervised classification and space selection method, the information of GuanzhongTianshui residential area was extracted, and space expansion was analyzed. The results show that the residential area of GuanzhongTianshui economic zone was increasing during 1990-2007, the area increased from 138 701.51 to 499 186.68 hm2 and the extension intensity was 15.29%. The proportion of residential area in the total cities area is increasing, and it shows that the middle is high and two sides are low in space. Central Guanzhong basin which has favourable natural condition and social condition is the axis of the whole economic belt. Weibei dry land has a huge development potential so it will be the important expansion area of GuanzhongTianshui economic zone.

GuanzhongTianshui economic zone; residential area; extension intensity; NDBI