The analysis between cotton NDVI and meteorological factors provides an important scientific basis for the timely and effectively to carry out the management work of cotton production. Based on MOD13Q1, rainfall, daily mean temperature, daily maximum temperature and daily minimum temperature during the growth period of cotton from 2000 to 2012, the author analyzed the variations characteristics of cotton NDVI and the effects of meteorological factors on cotton NDVI by using correlation analysis method. The results showed that: the cotton NDVI changed regularly with the growth of cotton, which increased rapidly and then decreased gradually. The correlation coefficient was small between the cotton NDVI and rainfall, and did not pass the significant test because the study area was irrigated agricultural area. The cotton NDVI and temperature strongly correlated, and the correlation coefficient was 0.7750-0.9500. Considering the correlation coefficients between cotton NDVI and accumulate temperature of different temperature types and their average values, the accumulated temperature of average temperature showed good correlation and stability with the cotton NDVI, the accumulated temperature of high temperature had little correlation with the cotton NDVI, the accumulated temperature of minimum temperature had a high correlation with the cotton NDVI. In short, the cotton NDVI could better reflect the cotton growth and had no correlation with rainfall, and the accumulated temperature of minimum temperature was one important factor for the growth of cotton.