In grazing systems, stocking rate (SR) is critical for the maintenance of grassland and livestock productivity. However, little is known about the relationship between the amount of supplementary feed used by livestock producers and SR, particularly across the pastoral areas of Inner Mongolia, China. This limits the understanding of whether feed supplements impact SR. Therefore, we studied 716 herding households using a two-round panel dataset collected across the five ecosystem types in Inner Mongolia. We used linear mixed-effects models to examine how the amount of supplementary feeds affects SR. Our results show that feed supplementation is not associated with increased SR across the grassland ecosystems. The amount of grains and pellets used by households was negatively related to SR, whereas the amount of hay was not correlated with SR. Overall, these results demonstrate that feed supplementation did not influence herders’ decision to overgraze. Thus, policies that underpin the scientific exploration of novel approaches to supplementary feed use in grazing systems are required. This could help achieve environmental sustainability and enhance the attainment of the desired modern livestock production system in Inner Mongolia and similar ecosystems.