Applying Tiandifu iron-sulfur complex fertilizer to rice fields in southern Hunan can increase rice growth and yield. The fertilizer helps rice plants tiller faster, grow better, and produce more grains. Compared to a popular local fertilizer, using Tiandifu fertilizer resulted in higher setting percentage, heavier grains, and increased rice yield per hectare. The yield of rice treated with Tiandifu fertilizer was significantly higher than that of rice without any fertilizer or with the local popular complex fertilizer. Overall, using Tiandifu iron-sulfur complex fertilizer can lead to a substantial increase in rice production in southern Hunan.