Nitrogen is the major limiting nutrient in cauliflower (Brassica oleraceae var. botrytis) which affects the growth and yield parameters. A pot experiment was carried out in IAAS, Lamjung Campus during Sept., 2018 - Jan., 2019 to determine the optimum nitrogen level. Six treatments (0, 150, 180, 200, 250, and 280) kg/ha of urea with the same level of Phosphorus, Potassium (120:80kg/ha) and FYM (20 t/ha) on two varieties (Snow Mystique and Jyapu Local) were used in a Completely Randomized Design with five replication. Half dose of N and full dose of P, K, and B were applied in basal dose. Application of 280 kg of urea/ha gave higher results in plant height (26.32 cm), plant spread (4103 cm2), leaf area (264 cm2), stem diameter (1.96 cm), number of leaves (22.10), root length (26.26 cm), girth of curd (49.46cm), fresh leaves weight (592.2 gm), fresh weight of stem and root (160.6 gm), curd weight (588.2 gm) while minimum results was obtained from control (0 kg urea/ha). The interaction effect of 280 kg urea on variety Snow Mystique gave the maximum value on plant spread (4904 cm2), stem diameter (2.15 cm), fresh leaves weight (816.8 gm) and fresh curd weight (759.3 gm).