To provide technical support and scientific basis for regional ecological protection and restoration, it is important to analyze the spatial differentiation characteristics of anthropogenic disturbance risk in ecological conservation redlines (ECRs) and to identify key risk factors related to human activities, as these elements are crucial for formulating targeted conservation strategies and mitigating human-induced ecological degradation. The ECRs in the Yangtze River Delta were taken as the research area in this study due to the region's rapid urbanization, high ecological value, and significant pressure from human activities, making it an ideal case for examining the interplay between development and conservation. Using the spatial Bayesian network with quantitative, probabilistic, and spatial features, a nonlinear quantitative evaluation model for human disturbance risk was constructed by selecting risk factors such as human activity hazard, human disturbance intensity, and ecological sensitivity, as this integrated approach allows for a comprehensive assessment of multidimensional risks while accounting for spatial heterogeneity and uncertainty. Then, this model was used to analyze the spatial differentiation characteristics of anthropogenic disturbance risk in the ECRs in the Yangtze River Delta, revealing distinct regional patterns that reflect varying levels of human pressure and ecosystem vulnerability. The results showed that the overall human disturbance risk level was relatively low, with risk proportions of low (0.76%), relatively low (69.60%), medium (17.88%), relatively high (9.59%), and high (2.21%), indicating that most areas within the ECRs remain under moderate to low risk but with notable localized high-risk hotspots. Furthermore, the human disturbance risk level was high in the south (Anhui and Zhejiang) but low in the north (Shanghai and Jiangsu), a spatial pattern driven by differences in terrain complexity, land-use intensity, and regional development policies. Meanwhile, the high-risk areas with prominent levels of human activity hazard, human disturbance intensity, and ecological sensitivity were mainly distributed in Zhejiang, Anhui, and their border areas, where mountainous terrain, agricultural expansion, and infrastructure development intersect to amplify ecological pressures. Among these risk factors, ecological sensitivity was the main driver for human disturbance risk, followed by human disturbance intensity and human activity hazard, suggesting that ecosystems with high natural vulnerability are more susceptible to degradation even under moderate human pressure. The key drivers of these risk factors were construction land hazard, elevation, and cropland sensitivity, highlighting the need for targeted management of urban sprawl, slope stability, and agricultural practices in ecologically sensitive zones. This research provides technical support for the prevention and control of anthropogenic disturbance risk in the ECRs in the Yangtze River Delta from the aspects of human activity regulation within the ECRs, the optimization and adjustment of the ECRs, and the prevention of construction land expansion, offering actionable insights for policymakers to balance ecological conservation with sustainable development in one of China's most economically dynamic regions.