Abstract: Based on the survey data of 21 stations in Lingdingyang in the summer of 2019, this study aims to analyze the distribution patterns and influencing factors of the dissolved heavy metals, and discusses the impact of estuarine dynamics and eutrophication on the heavy metals. Used correlation analysis, principal component analysis-multiple linear regression model (PCA-MLR) to quantitatively analyze the sources and contribution rates of heavy metal pollution. The results show that Cr, As, Cu, and Zn exhibit a decreasing trend from the upper estuary to the mouth, varying from 0.17-0.95, 2.8-5.0 3.59-12.66, and 1.02-4.05 μg·L⁻¹, respectively; while Pb, Hg, and Cd show different trends, varying from 0.16-1.72, 0.014-0.029, and 0.04-0.09 μg·L⁻¹, respectively. The spatial distributions of the seven heavy metals is significantly different, related to human pollution, industry, agriculture, and domestic sewage discharge in the coastal areas. Based on the eutrophication assessment, the nutrient level of the Lingdingyang Bay is classified as “medium to high” eutrophication level, which is significantly related to the distribution characteristics of heavy metals (such as As, Cu, and Zn). The results of ecological risk assessment show that the heavy metals in the study area are generally at a “mild to moderate” pollution level, with Cu, Zn, and Cd being the main pollution elements. Pearson correlation analysis showed that As, Zn, and Cu originate from similar pollution sources, Cr and Hg have similar sources, and Pb and Cd come from different pollution sources than the above. The PCA-MLR results show that there were four main sources of heavy metals in the surveyed sea area, with industrial sources contributing the most (29.5%), followed by transportation sources (25.1%) and natural sources (23.0%), and agricultural pollution sources contributing the least (22.4%). The results of this study are of great significance in revealing the mechanism of heavy metal migration and transformation in estuarine areas under the influence of strong human activities. It also provides important support for the overall prevention and control of pollution by land and sea in the Pearl River Estuary and the water security of the Guangdong-Hong Kong-Macao Greater Bay Area.