Soil microbial communities, being at the interface of plant-soil feedback systems, can play a pivotal role in facilitating ecosystem response to the drivers of global environmental change, including invasive alien species (IAS). Studies evaluating the effect of plant invasion on soil microbial communities along altitudinal gradients can provide novel insights regarding the spread and impact of IAS and elevational range shifts in response to ongoing climate warming in mountains. In this study, we used metagenomic tools to investigate the impact of invasive Leucanthemum vulgare on taxonomic composition, relative abundance, alpha and beta diversity of soil microbial (bacterial and fungal) community, physicochemical properties and their interaction between invaded and uninvaded plots selected across multiple sites along an altitudinal gradient in Kashmir Himalaya. We found that the invasion by L. vulgare shifted composition, relative abundance, alpha and beta diversity of soil microbiome significantly in invaded plots. The relative abundance of soil microbial communities interestingly showed an increasing trend along the altitudinal gradient. The soil physicochemical properties were significantly correlated with microbial community abundance with temperature, K, pH, EC and Fe being the dominant determinants. Also, we found a significant effect of soil physicochemical properties on the microbial community abundance along the altitudinal gradient. Our findings unravel the plant invasion-induced shifts in the underground soil microbiome and physicochemical properties, which improve our understanding of plant invasion impacts on belowground biotic and abiotic components and can contribute in guiding integrated management of invaded mountain landscapes globally.