The rate of degradation of lakeshore zones has been greatly accelerated by human activities and climate change. The method of plant functional traits can quantify plant characteristics and predict plants responses to externally environmental disturbances, and this method can help us understand the adaptive mechanisms of degraded lakeshore wetland plants in response to environmental changes, which is important for the restoration and reconstruction of lakeshore wetland ecosystem vegetation. In this paper, the leaves and roots of seven dominant plants, Phragmites australis, Leymus secalinus, Ranunculus japonicus, Potentilla anserina, Suaeda glauca, Salicornia europaea and Calamagrostis epigeios, were selected in the lakeside wetlands of typical lakes on the Inner Mongolia Plateau to study the change patterns of 11 functional traits of different wetland plants and their relationships with environmental factors. The aim is to investigate the differences in species distribution and functional traits of wetland plants in the lakeshore zone under the influence of environmental changes, and the adaptation strategies of wetland plants in different lakeshore wetland habitats. Based on the assessment of interspecific and intraspecific variation in plant functional trait, the effect of environmental factors on plant functional traits was analyzed using RLQ combined with Fourth-Corner analysis. The results showed that the functional traits of the seven dominant plant species in the lakeshore zone wetlands of the Inner Mongolia produced different degrees of interspecific and intraspecific variation in order to adapt to different environmental influences, and the plant height, leaf carbon concentration, leaf nitrogen concentration, leaf carbon to nitrogen ratio, specific root length, root tissue density and root nitrogen content of the plants in the lakeshore zone wetlands were sensitive to the environmental changes. In the lakeshore zone wetland environment, soil pH was negatively correlated with leaf dry matter content; soil salinity was negatively correlated with plant height, leaf carbon concentration and leaf carbon to nitrogen ratio, while positively correlated with leaf nitrogen concentration and root tissue density; soil nitrogen concentration was positively correlated with plant height and negatively correlated with root length; soil carbon to nitrogen ratio was negatively correlated with plant height and leaf carbon concentration, but positively correlated with root length; soil bulk density was negatively correlated with root nitrogen concentration. This study shows that the functional traits of wetland plants in the lakeshore zone of the Inner Mongolia Plateau are strongly influenced by the environment, and lakeshore zone plants have adopted different trait strategies to adapt to their environment.