Measurement of CO₂ concentration with high accuracy and precision is essential for monitoring local emission sources of greenhouse gases at regional and city scales. Based on Fourier transform spectroscopy and near-infrared solar absorption spectra collected by portable FTIR spectrometer, the column concentration of CO₂ in the Hefei area from September 2016 to May 2020 was retrieved using the nonlinear least-squares algorithm. As the observation results show, the column concentration of CO₂ has obvious seasonal variation, with the maximum value in spring, the fast decline in summer, and the minimum in autumn. The daily average value of XCO₂ is between (401.23±0.60) and (418.41±0.31) ppm, while the monthly average value shows a seasonal amplitude of 6.96 ppm during 2017. XCO₂ showed an increasing trend during the observation, with an annual growth rate of (2.71±0.66) ppm·yr^-1. In order to verify the accuracy and reliability of portable FTIR spectrometer observations, we compared the observations with the high-resolution FTIR measurements. It is found that the mean deviation of XCO₂ was about 1.32 ppm, the linear fitting coefficient was 1.08±0.03, and the correlation coefficient r was 0.97. Further, our data are compared with GOSAT satellite data, the average deviation of the two data is (0.63±1.76) ppm, and the correlation coefficient r is 0.86, showing a high correlation between ground-based data and satellite data. Also, ground-based observations in Shanghai were compared with the simultaneous observations in Hefei. The results showed that the variation of XCO₂ in Shanghai is similar to our results. The daily average of XCO₂ in Shanghai is between (411.87±1.07) and (416.63±1.70) ppm, and the value is between (415.09±0.84) and (417.80±0.67) ppm in Hefei in autumn. It is found that XCO₂ in Hefei was slightly higher than that in Shanghai during the observation. The results provide the data for tracking carbon sources and sinks of greenhouse gases in the Hefei area.