The paper used TM image data, land use vector data, and China's high spatial resolution grid data(CHRED) of Urumqi's center area in 2005 and 2012, and studied the change of Urumqi's ecosystem and environment with the conversion of land use. The method of land use conversion, ecosystem service value assessment and carbon emission accounting were employed in this study. Results showed that land use conversion was significant, among which the land conversions of garden land, grassland, urban village, industrial and mining land and unused land were more obvious. The unused land showed the greatest change(1.033×105 hm2) which indicated that the degree of land development in the study area was higher. With the conversion of land use, the value of ecosystem services showed an increasing trend. The net EVS value rose by 892.273 2 million yuan. The land conversion of garden land, grassland and water area contributed most to the increase of ecosystem service value. There was an uptrend in the carbon emission intensity of land use. The highest carbon emissions were induced by urban villages and industrial and mining land. Although the net ecosystem service value of the land use conversion was increasing, the change of land carbon emission intensity was more quickly than the change of the ecosystem service value. Therefore, the balance between the adjustment of land use structure and the protection of the ecological environment should be considered by the government in the low-carbon construction of Urumqi.