Dissolved organic matter (DOM) in the water column constitutes a vital component of the carbon cycle within lake ecosystems. To investigate the impact of urbanization on DOM characteristics of urban lakes, we took Lake Dishui, the largest artificial urban lake in China, as a case study. We examined the temporal and spatial variation characteristics of chromophoric dissolved organic matter (CDOM) in Lake Dishui and its surrounding water system from winter to summer (January, March, and July) using ultraviolet-visible absorption spectroscopy and three-dimensional fluorescence spectroscopy. The influence of the urban construction, of Lingang New City, Shanghai, on the composition and source of CDOM in water was preliminarily explored. The results were as follows: ①Tyrosine-like C1, tryptophan-like C2 and terrestrial humic-like C3 were identified through parallel factor analysis (PARAFAC). The contribution of protein-like (C1 and C2) components to fluorescence intensity decreased, while the contribution of C3 increased. ②Most values of the autogenetic index (BIX) were ＞1.0 or close to 1.0, and the fluorescence index (FI) ranged from 1.4 to 1.9, indicating that the characteristic of CDOM during the temperature rising (from winter to summer) were influenced by both endogenous and exogenous inputs, and biological activity (microbial source) was the main source and had strong autogenetic characteristics. Influenced by exogenous input from rainfall or surface runoff, the relative concentration of CDOM was diluted and decreased in the spring and summer seasons. In January, a(254) was significantly higher than that in March and July, and the molecular weight of CDOM was low. ③The land use types of river channels around the lake were primarily residential areas, newly built parks, and building sites under construction with 0.8＜BIX＜1.0 or BIX＞1.0, indicating high biological metabolic activity in the water body and significant impact of CDOM on human activities. The C3 fluorescence intensity gradually decreased from the river channels to the lake district, indicating that terrestrial humic-like substances mainly entered Lake Dishui through the river channel. ④The fluorescence parameters BIX and FI were significantly correlated with protein-like components and nitrogen concentrations, which can serve as potential indicators for future water quality monitoring of Lake Dishui. Our study suggests that rainfall, runoff input, land use type, and rapid urbanization collectively affect the CDOM characteristics of the lake. The relevant results can provide a basis for further understanding the composition characteristics and water environment management of dissolved organic matter in urban water bodies under the background of urban development.