Nitrogen fertilization is one of the main management strategies for continuous pasture management with high productivity. We examined the effects of nitrogen fertilization on the morphogenic, structural, and tillering dynamic characteristics of Tanzania grass in the Amazon region in the state of Pará, Brazil. The study was conducted using a randomized block design with six treatments (0, 100, 200, 300, 400, and 500 kg N ha−1 year−1) and five replicates. The treatments were performed during the rainy season in 2016 and 2017 using urea as the nitrogen source. The leaf elongation rate was increased by 68.5% compared with that of the control treatment (p p −1 (p p −1.