Sorghum is a multiple purpose cereal that can be used for different products such as food, feed, fiber and fuel. In this study, the effects of nitrogen fertilizer and ethephon concentration on growth parameters, carbohydrate content and ethanol production on sweet sorghum were determined. Four nitrogen fertilizer (0, 100, 200, 300 kg urea ha−1 and four ethephon concentration (0, 800, 1000, 1200 ppm) assigned as main plots and sub main plots, respectively with three replications. Results showed that plant height and plant diameter increased up to 100 kg urea ha−1. Plants were thicker with ethephon application. Highest dry biological yield and dry stalk yield were obtained with 300 kg ha−1 urea and 1,200 ppm ethephon. Juice volume was increased by application of urea up to 100 kg ha−1. More urea application did increase juice volume. Juice volume was highest with the application of 1,200 ppm ethephon. Brix, total carbohydrate content and sucrose were highest with the application of 300 kg ha−1 urea and 1,200 ppm ethephon. On contrary invert sugars were lowest at 300 kg ha−1 urea and 1,200 ppm ethephon. Ethanol yield was highest at 300 kg ha−1 urea and 1,200 ppm ethephon. There is a significant correlation between ethanol yield and stalk yield, juice volume, brix, total sugar and sucrose content. Based on the results, the highest ethanol yield was obtained with the application of 300 kg urea ha−1 and 1,200 ppm ethephon.