Nitrogen optimization is a biggest challenge in sustainable crop production especially in fresh vegetable production. For this reason, a study was carried out for two consecutive seasons to investigate the effect of nitrogen levels on the growth, yield and nitrogen use efficiency of broccoli under the climatic conditions of Dera Ismail Khan district of Khyber Pakhtunkhwa (KPK), Pakistan. The nitrogen levels used in the study were 0, 50, 100, 150, 200, 250 and 300 kg N ha^-1. The experiment was laid in randomized complete block design (RCBD) with three replicates. Parameters studied were days taken to maturity, leaf chlorophyll content, leaf number plant^-1, leaf area index, head weight, head diameter, number of axillary shoots, weight of axillary shoots, total yield (t ha^-1) and marketable yield (t ha^-1). Results revealed a linear significant increase in growth parameters under study by addition of nitrogen at an increasing rate from 0 to 300 kg ha^-1 during both the years. Regression analysis of the data for all the parameters measured during both the years showed that the linear model was the best fit to the data of all parameters. The coefficient of determination for all linear models showed a strong relationship between the nitrogen rates and various parameters of broccoli. Comparing the data of two years on various parameters the t-test of significance showed that both the years were at par with each other for all the parameters studied.