Nitrogen is a vital element for plant growth, playing a crucial role in photosynthesis and protein synthesis. The bio-stimulant "Utrisha N," which contains the bacteria Methylobacterium symbioticum, has the potential to enhance nitrogen availability by fixing atmospheric nitrogen, thereby promoting sustainable agricultural practices. While it has been evaluated in other row crops, its application in vegetable crops remains untested. This study examined the effects of the foliar application of "Utrisha N" on yield, nitrogen metabolism, and phytochemical profiles under various nitrogen conditions. The results indicated that the foliar application of "Utrisha N" during the developmental phase of spinach significantly increased both fresh and dry biomass and chlorophyll content. No significant changes in nitrogen mineral metabolism were observed regardless of nitrogen availability. We assessed nitrogen assimilation by calculating the percentage accumulation of amino acids in the vegetative tissues. The differential expression of genes related to nitrogen metabolism influenced by Methylobacterium symbioticum is currently being analyzed. This study's results will help clarify the potential benefits of Methylobacterium in improving nitrogen metabolism and boosting spinach productivity.