A field study was conducted during Rabi season 2022at the Horticultural Research Farm, Mangalayatan University, Jabalpur to study the effect of foliar application of nano urea and urea on growth and yield of onion. The experiment was laid out in RBD with three replications and consisted of 9 treatments viz., T1-100% RDF (100:50:50 kg NPK ha1), T2-75:50:50 kg NPK ha-1 + foliar spray of 0.4% nano urea on 30 and 60 DAT, T350:50:50 kg NPK ha-1 + foliar spray of 0.4% nano urea on 30 and 60 DAT, T4-75:50:50 kg NPK ha-1 + foliar spray of 0.4% nano urea on 30 DAT, T5-50:50:50 kg NPK ha-1 + foliar spray of 0.4% nano urea on 30 DAT, T6-75:50:50 kg NPK ha-1 + foliar spray of 0.5% urea on 30 and 60 DAT, T7-50:50:50 kg NPK ha-1 + foliar spray of 0.5% urea on 30 and 60 DAT, T8-75:50:50 kg NPK ha-1 + foliar spray of 1% urea on 30 and 60 DAT, and T9-50:50:50 kg NPK ha-1 + foliar spray of 1% urea on 30 and 60 DAT. Each treatment showed their significant effects on the recorded growth and yield parameters. Among all the treatments, treatment T2 with 25% reduced nitrogen application plus foliar spray of 0.4% nano urea on 30 and 60 DAT recorded maximum plant height on 90 DAT (57.82 cm),number of leaves (9.13), equatorial diameter (5.51 cm), polar diameter (5.17), average bulb weight (69.56 g), bulb yield (336.40 kg) than other treatments.