Urbanization is an important indicator of regional economic development and social progress. Studying urbanization level is of great significance to urban scientific development and efficient decision-making for government. The night light data contains information on human activities and economic and social development, which makes up for the uncertainties and lags of the index method. It can more intuitively reflect the level of urbanization and provide new ideas for urbanization research. Existing studies have used night light data to analyze the macro-scale urbanization level, but because the time ranges of the DMSP-OLS data and NPP-VIIRS data are short, the time scales of the two data are discontinuous, and the spatial resolution is inconsistent with the radiation resolution, so it is mainly focused on the use of a kind of night light data to study the level of urbanization, and the study time span is short. In addition, although studies have shown that there is a strong correlation between large-scale socio-economic activities and nighttime lighting conditions, at a smaller scale, this correlation is greatly affected by regional economic development and the resolution of light data. There are higher requirements for estimation accuracy, so it is necessary to use actual data to prove the rationality of using night light data to estimate county-level urbanization levels. This paper uses DMSP-OLS and NPP-VIIRS night light data to estimate the county-level urbanization level in Anhui Province from 2006 to 2015, and provides theoretical support for night light data in the study of long-term serial urbanization. First, calculate the average night light index of DMSP-OLS and NPP-VIIRS respectively, and take the NPP-VIIRS light index as the independent variable and the DMSP-OLS light index as the dependent variable. Fit and establish the corresponding relationship between the two types of lighting data, and obtain the DMSP-OLS average night light index of each district and county in Anhui Province from 2006 to 2015.Then urbanization indicators are selected from the four aspects of population, economy, social life and agricultural mechanization, using analytic hierarchy process to calculate the level of urbanization based on statistical data. Finally, the correlation and linear regression analysisbetween light index and urbanization level based on statistical data is analyzed to show the consistency of time and space distribution oflightintensity and urbanization level based on statistical data in all districts and counties of Anhui Province. The results show that the average nighttime light index highly correlatesto urbanization level based on statistical data at the county level with the correlation coefficient of 0.91(P<0.05) and the coefficient of determination of linear regression of R²=0.82. The spatial and temporal distribution of the light index and the urbanization level based on statistical data are basically the same. Spatially, the overall urbanization level in Anhui Province is unevenly distributed, showing a pattern of high in east and low in west; temporally, the urbanization level from 2006 to 2015 showed year by year. The urbanization level of developed urban areas such as Hefei City and Maanshan City is growing faster, while less developed areas such as Huoqiu County and Shou County are growing slowly.