’Jiza 355’ was used as materials and a field experiment was carried out to study effects of nitrogen, phosphorus and potassium application on grain yield of sorghum. A model between levels of fertilizer and grain yield was established. Optimal fertilizer application was obtained. The results proved that yield of sorghum was the highest under the conditions of pure nitrogen 201.3 kg/ha, P₂O₅ 124.5 kg/ha, K₂O 95.9 kg/ha. The effect of half of the nitrogen fertilizer applied as base fertilizer and half as topdressing was better than one-time application of nitrogen fertilizer.