Simultaneous measurement of black carbon (BC) and non-refractory PM1 aerosol chemical compositions was performed in Autumn, 2016 at a suburban site of Hong Kong. A thermodenuder (TD) was employed at different heating temperatures to remove semi-volatile aerosol fractions to varying degree. Light absorption enhancement (Eabs) of BC by semi-volatile coatings at seven wavelengths was evaluated, and the coating fractions was further analyzed. Result showed overall Eabs was 1.58 ± 0.13 (470 nm)–1.64 ± 0.16 (660 nm) measured at 280°C, whereas Eabs increased very little from 50°C (1.02–1.04) to 200°C (1.13–1.20). The lensing-effect-related Eabs was probably attributed to the presence of ammonium and sulfate. Furthermore, the ratio of coating thickness to BC core radius was around 1.0–2.0 based on Mie calculation. This work evaluated the Eabs by coatings in Hong Kong and implied the BC mixing state, thus could provide critical reference for climate model on the role of aerosol in global warming.