Abstract: The application includes a Brevundimonas and a use thereof in tea plant planting, belonging to the technical field of microorganisms. The Brevundimonas is Brevundimonas sp. AnNong-1 which is preserved in China Center for Type Culture Collection with a preservation number CCTCC M 20221537. The culture solution of the strain can significantly increase the function of the total amount of L-Theanine in first and second leaves of tea plants after being inoculated around a distance of about 5 cm from the roots of tea seedlings. The Brevundimonas sp. AnNong-1 of the present invention is easy to operate in fermentation conditions and can also be used for preparing a natural microbial fertilizer, which can significantly increase the content of L-Theanine without greatly affecting the content of tea polyphenol, thereby providing a choice for the tea market. The microbial fertilizer is an environmental-friendly fertilizer, and can greatly reduce environmental pollution.