Soil physical and chemical properties are important indicators to measure soil quality, and soil microorganisms can sensitively reflect changes in the soil environment. The impact of raising chickens under the forest on the soil environment under the forest can be fed back through the changes in both. However, previous studies on the effects of chicken breeding in Masson pine forests on soil physical and chemical properties and the diversity of soil microbial communities are rare. Thus, the design of this study was centered on the chicken coop, within 50 m, and every 10 m is a sample point. A five-point sampling method was used to study the impact of chicken flock activities on soil physical and chemical properties and microbial communities at different distances. The results showed that soil pH and nutrient content presented a decreasing trend with increasing distance, with significant differences among groups. Soil bulk density, water content and organic carbon content had opposite trends. The diversity of the soil microbial community showed a decreasing trend with increasing distance, in which bacterial diversity was higher than fungal diversity; Proteobacteria, Acidobacteria and Actinobacteria were the dominant bacteria; and Arthropoda and Ascomycota were the dominant phyla. This study shows that raising chickens under the forest has improved the forest environment, and a certain frequency of chicken activity or breeding density may be the key factor affecting the forest environment. When applying and promoting raising chickens under the forest, we should pay attention to the appropriate breeding density.