Aerosol samples were collected at urban and rural sites in Chongqing, China, from December 2015 to July 2017, and then the spatial and seasonal variations of light absorption properties and implications of brown carbon (BrC) in aerosols in this area were systematically investigated, and the radiative forcing of BrC was evaluated. The results show that the average light absorption coefficient b405,BrC, contribution to aerosol light absorption, and mass absorption efficiency of BrC at 405 nm in winter were (13.0±9.0) Mm－1, (24.5±6.1)% and (0.9±0.2) m2·g－1 respectively, about 11.3, 2.9 and 3.4 times of those in summer. The average b405,BrC at urban site (YB) in summer and winter were 2.8 and 1.8 times of those at rural site (JY) respectively. However, the absorption ngstrm exponent (E =1.2±0.1) and the contribution to aerosol light absorption of BrC at 405 nm (16.7±5.9)% at YB weresignificantly lower than those at JY ((1.6±0.2) and (32.3±6.3)%, respectively). The relationships between b405,BrC and the indicators of pollution sources indicated that the light absorption properties of BrC were mainly affected by the formation of secondary organic aerosols (SOA) in summer, while mainly affected by biomass burning, coal burning and the formation of SOA in winter. Compared with those in summer (p> 0.1), the significant correlation between b405,BrC and NH4+ concentrations (p< 0.001), as well as the significant correlations between E and the mass fractions of NO3－ and NH4+, were observed in winter. The shape of fit line between E values and φ in winter was similar to that of combustion chamber results of biomass burning, indicating that BrC light absorption was mainly affected by biomass burning and the aged BrC produced from the reactions of organic compounds with NO3－ and NH4+ during winter. The fractional contribution of radiation absorbed by BrC was (29.1±5.8)% in 405～980 nm and (60.8±13.7)% in 405～445 nm in winter, about 2.9 and 3.2 times those in summer, indicating that the radiation absorbed by BrC was the main contributor affecting the radiative balance during winter, especially at short wavelengths.