The biggest threat to human civilization now is climate change, which will cause severe food and water scarcity in the near future. Change in climate would lead to increased warming coupled with untimely rains and will be highly detrimental for crop productivity. Bio-stimulating role of Plant Growth-Promoting Rhizobacteria (PGPR) has already been explored and found out to be a green solution for dealing with abiotic stress-related problems. These PGPRs play fundamental role in plant adaptation to the environmental factors by modulating important physiological processes during stress. Key pathways like Photosynthesis, ROS scavenging, Nitrogen metabolism, etc. are regulated at molecular level for amelioration of stress conditions. It has also been established by modern researchers that PGPR inoculation drives differential gene expression and enzyme production. In the present review, we have reported the current knowledge gained on molecular aspects of stress adaptation by PGPR strains.