The culture of rice has great potential to constitute the production systems of annual perennial crops, mainly in small properties. This allows this system to integrate with other activities such as the dairy industry, taking advantage of the milk by-product, reducing the environmental liability for disposal in the environment. Therefore, the objective was to evaluate the growth and productivity of rice grains under different doses of acid milk serum (0 m3 ha-1, 5 m3 ha-1, 10 m3 ha-1, 20 m3 ha-1, 50 m3 ha-1, 100 m3 ha-1, and 150 m3 ha-1), in soil applications with monitoring of fertility and electrical conductivity levels. The rice was sown in the UFLA experimental field, using the BRSMG Esmeralda lineage. Seven different doses were used, divided into two applications via soil. No cover fertilization was carried out. Yield and crop growth variables were determined by monitoring the nutrient content in the soil profile and the sodification and salinization capacity of the residue. It was found that the increase in serum doses increased the electrical conductivity and the percentage of exchangeable sodium by 1.75 and 7.75 compared to the control, but did not cause the process of sodification and salinization of the soil. As acid milk serum is a significant source of potassium, its use in the soil did not promote significant grain yield. It was concluded that the acid milk serum in the doses used did not cause sodification or salinization of the soil. This residue is the safe dose that can be used as potassium and nitrogen. The acid milk serum in the tested conditions did not increase the growth of the culture.