Plant litter is an important part of the material cycle in wetland ecosystems. With the gradual intensification of global climate change, the impact of climate warming on the decomposition of plant litter in wetlands has attracted widespread attention. In this study, the decomposition processes of two typical plant litters, Phragmites australis and Typha domingensis, in the wetland of Nansi Lake, Shandong province, were comparatively studied by the litter bag method, and the effects of atmospheric warming (2.0±0.5)℃-(4.0±0.5)℃ on the decomposition characteristics of litter and bacterial community structure were simulated by using an Open-top chamber (OTC). The results showed that warming significantly accelerated the decomposition rate of the litter of both plants, while Lignin/N and Cellulose/N were important factors affecting the decomposition rate of the litter, and were significantly negatively correlated with the decomposition rate. Warming significantly increased the abundance and diversity of bacterial communities, with carbon being the driver of changes in the abundance of bacteria such as Firmicutes, while Lignin and Lignin/N were the drivers of changes in the abundance of bacteria such as Bacteroidota. The bacterial community co-occurrence network showed that the bacterial community network of litter decomposition was mainly composed of symbiotic relationships under warming conditions. Climate warming increased the interrelationships and reciprocity among bacteria, accelerated the decomposition process of plant litter, and thus affected the carbon balance of the wetland ecosystem.