Abstract: Surface and bottom seawater samples were collected in the Changjiang (Yangtze River) Estuary and the adjacent area in March and July 2019. Concentrations of dissolved organic carbon (DOC) and absorption spectra of chromophoric dissolved organic matter (CDOM) were measured in those samples. During both cruises, concentrations of DOC and abundances of CDOM (reflected by the decreasing a₂₅₄ values) generally decreased from land to sea. At the same time, the decreasing CDOM aromaticity (reflected by the decreasing SUVA₂₅₄ values) and the decreasing overall molecular weights of CDOM (reflected by the increasing S_275-295 values) were also found. DOC and CDOM generally showed significantly higher abundances, higher aromaticity, and higher molecular weights at the surface layer than those at the bottom of the same station. Moreover, the two components showed higher concentrations or abundances and aromaticity in July than in March, but molecular weights had no significant change. During each of the two cruises, DOC concentrations and CDOM parameters (a₂₅₄, SUVA₂₅₄, and S_275-295) all showed significant correlations with salinity, in which S_275-295 showed positive correlations while the others showed negative correlations. From the correlation coefficient values (R²), it can be concluded that DOC and CDOM were more conservative in March than in July, and they were more conservative at the bottom than at the surface in July.