Soy has high plasticity, which expands its capacity to adapt to different environmental and management conditions, through morphological changes in production components. Thus, the objective was to evaluate the effects of different densities of soybean cultivar BRS 8381 on agronomic characteristics. The experiment was implemented and conducted in a Cerrado area, in the Agua Boa of Embrapa Roraima experimental field. A randomized block design was used in a 2*4 factorial scheme, with four replications. The treatments consisted of two years of soybean cultivation (2015 and 2016), sown in four plant densities (10, 14, 18 and 22 plants per linear meter). Agronomic characteristics were evaluated: plant height; height of insertion of the first pod; stem diameter; number of nodes on the stem; number of pods per plant; number of branches per plant; dry mass of the plant; harvest index and grain yield. The highest average productivity of 'BRS 8381' soybeans in the Cerrado area of Roraima is obtained with a population of 387.448 plants per hectare. 'BRS 8381' plants at density 22 plants m -1 linear are not suitable for the Cerrado conditions of Roraima. The cv. BRS 8381 is influenced by rainfall and temperature factors in the Cerrado conditions of Roraima.