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The interannual and interdecadal changes of air temperature and the correlation with totaland lowcloud covers are analyzed, by means of the observed data of surface air temperature from 24 stations over the Loess Plateau region of Shaanxi in recent 50 years. The results indicate that mean temperature increased in a wavy way, especially after the 1987s; the interannual changes of air temperature in the northern sanddrifting areas were obvious, with the warming amplitudes decreasing from north to south; since 1957, the annual mean total cloud cover gradually decreased, and the decreasing tendency of low cloud cover was more obvious than that of the total, but the total cloud cover increased after 2000. The correlation analysis indicates that there was negative relation between annual mean air temperature and total and low cloud covers in the Loess Plateau region of Shaanxi, both passed the test with the significant level being 0.001 and the low cloud cover had more significant relation with temperature; there was obvious positive relation between precipitation and total and low cloud covers; meanwhile, the correlation coefficients between air temperature and totaland lowcloud covers were different greatly in different regions and seasons, but there was significant correlation between cloud cover and precipitation.