The main task in this research was to determine the number and changes of nematode communities in the soil under the influence of liquid chicken manure in onion and pea production. The experiment was set up in the spring of 2022. in the family garden in Bilje. An area of 2.25 m2 was prepared, and the crops chosen were peas and onions in a consociation (one row of peas, one row of onions alternately). The preparation Ekovital, based on liquid chicken manure, was applied 3 times during the growing season to part of the plot (treated part), while the same amount of clean water was applied to the control part. Soil samples for nematodes were taken on two occasions, before the growing season in April 2022, and before harvest in June 2022. Nematodes were separated from the soil using Baerman's lefter method, counted and determined to genus. The results showed a greater biodiversity of nematode genera in the treated, compared to the control part of the plot by 11 %, a decrease in the share of harmful phytoparasitic nematodes compared to the control, and an increase in beneficial nematodes from the group of omnivores and predators. Nematological indices - soil maturity index (MI), soil enrichment index (EI) and structural index (SI) also had higher values, i.e. they indicated a more stable ecosystem and better quality soil in the treated part of the plot compared to the control. After harvesting, a 22 % higher yield of peas and a 20 % higher yield of onions were found in the part of the plot that was treated with the preparation based on liquid chicken manure compared to the control treatment. From all of the above, we can conclude that the preparation based on liquid chicken manure increased the biodiversity of nematodes in the soil, improved their trophic structure, and had a positive effect on the yields of peas and onions.