The research relevance is predetermined by the need to study strains of Bacillus subtilis bacteria that have a positive effect on plant growth and development and exhibit a stimulating effect at optimal bacterial loads. The research is of great importance for agriculture, ecology, and sustainable development. The research aims to determine the effect of new strains of B. subtilis (H3, H10, H13, H36, H38, H40, H43, H45) on the development of winter wheat (Triticum aestivum L.) seedlings when inoculated with inoculated crops. Laboratory, vegetation, and mathematical and statistical methods were used in the study: deep cultivation of strains, roll method of germination of test plant seeds, and data processing using Statistica 8.0 and MS Excel. The results of the model experiment on the effect of culture liquids of B. subtilis strains under different technological forms and dilutions on the growth and development of wheat test plants are summarised. It has been established that at dilutions of 1:10, 1:50, 1:100, and 1:500, the stimulating effect of bioagents is observed, and the maximum effect is achieved at a dilution of 1:100. It has been shown that the greatest positive effect on wheat seed germination was observed for B. subtilis inoculants applied to seeds in mature technological forms (spore culture, 2.0 x 107 cells per seed). The germination energy of Triticum aestivum L. seeds increased by 96.5% when interacting with B. subtilis inoculants, and the raw weight of seedlings increased by 84.0-109.6% depending on the experiment variant compared to the control, which indicates the growth-stimulating properties of the new strains. It was proved that the use of mature cultures of B. subtilis H38, H40 and H45 resulted in an increase in root weight by 4.8-11.3% compared to the control without bacterisation. When treated with culture fluids of B. subtilis H3, H10, H13, H36, and H43 in the form of vegetative cells, the root mass decreased by 11.8-44.0% compared to the control. The use of the studied strains of B. subtilis effectively affects the development of winter wheat and is a promising inoculant with a growth-stimulating effect. The practical significance of the study is to understand and determine the potential benefits of using Bacillus subtilis bacterial strains to enhance the growth and development of plants, in particular winter wheat (Triticum aestivum L.)