These data include those directly collected from 140 wastewater treatment plants in China.The annual average monitoring data of anaerobic digestion and dewatering processes in Maidao wastewater treatment plant of Qingdao in Shandong Province of China, which is the most typical wastewater treatment plant that uses anaerobic digestion technology to treat sewage sludge in the country, were used in this study When using this dataset in life-cycle assessments (LCA), it is crucial to ensure that the scope of the LCA appropriately reflects the management of one tonne of dry sludge as the functional unit. Consider factors such as geographical relevance to the Maidao sewage treatment plant and the technological applicability of dewatering processes. Users should also account for possible variations in emissions and resource usage based on local operating conditions. The dataset is specialized and may not be applicable to dissimilar wastewater treatment contexts or different sludge treatment technologies.