Maize growth and yield in Southern Ethiopia were studied by applying different levels and times of nitrogen fertilizer. The research found that using 69 kg ha-1 of nitrogen in three splits resulted in the highest grain yield of 9037 kg ha-1, while the control treatment had a lower yield of 4316 kg ha-1. The study showed that the timing and amount of nitrogen application significantly affected maize growth, yield, and economic benefits. This information can help farmers in Arba Minch improve their maize cultivation practices for better yields and profits.