<p>Soil salinization has significant negative effects on arable lands and crop productivity worldwide. Plant growth–promoting rhizobacteria (PGPR) have the capability to establish mutualistic associations with plants, resulting in the increase of plant growth under abiotic stress. PGPR strain <i>Pseudomonas</i> PS01 was previously isolated from the rhizosphere of maize. In this study, PS01 inoculation significantly enhanced biomass accumulation in <i>Arabidopsis</i> seedlings and increased maize seed germination and shoot and root biomass, as well as photosystem II efficiency under salt stress. Whole-genome sequencing of PS01 revealed multiple genetic determinants associated with salt tolerance, including 1-aminocyclopropane-1-carboxylic acid (ACC)-deaminase, genes involved in adhesion and biofilm formation, genes involved in the synthesis of exopolysaccharide and alginate, genes involved in Na⁺/K⁺ transporters, the tryptophan-dependent indole-3-acetic acid (IAA) synthesis pathway, and gene clusters encoding the synthesis of osmoprotectants. Taken together, PGPR strain PS01 could enhance the plant growth and salt stress tolerance through various pathways, which provide a foundation for deciphering the molecular mechanisms of PS01-mediated plant salt tolerance and for promoting the application of this strain.</p>