Dialysis nurses face complex and demanding working conditions. Due to demographic changes, the number of dialysis patients has increased, while the number of skilled personnel is expected to decrease, leading to tremendous increases in quantitative demands in the near future. Against the background of increasing workload, focusing on the provision of job resources is considered a promising approach because resources can buffer the negative effects of job demands. The aim of this study is to investigate whether different job resources—in particular influence at work and feedback—play a buffering role in the relationship between job demands and employee well-being. The study used a cross-sectional paper–pencil survey design. Data were collected from 951 dialysis nurses working in dialysis facilities in Germany between October 2010 and March 2012 using validated measures of quantitative job demands, job-related resources (influence at work and feedback), and cognitive stress symptoms. To test the moderating role of resources, we applied hierarchical regression analyses. The findings indicate that feedback buffers the relationship between quantitative demands and well-being; that is, the positive relationship between quantitative demands and cognitive stress symptoms was weaker when feedback was high. However, we found no buffering role of influence at work. The results suggest that feedback is a promising resource that may buffer the negative impact of quantitative demands on well-being of dialysis nurses. The findings offer new approaches for training nurses and implementing a feedback culture.