Field experiments were carried out in 2013 and 2014 at Iwuru, Cross River State, in Southern Nigeria to determine the effect of nitrogen fertilizer on the growth and yield of three rice varieties. The experiment was laid out in a randomized complete block design fitted in a 3x4 split-plot, replicated three times. The results showed that the application of 90kgha^-1 significantly (p<0.05) produced higher agronomic parameters (plant height, number of leaves per sucker, weight per tiller and leaf area), compared with nil fertilizer. The application of 90kgha^-1 had higher values of agronomic parameters than the application of either 60 or 120kgha^-1 under similar experimental conditions. There was 18.3% unit drop in grain yield when fertilizer rate was increased from 90 to 120kgha^-1, indicating that grain yields obtained by applying 90kgha^-1 were significantly, higher than values obtained from the application of 120kgha^-1. Varietal differences were significant (p<0.05). The varieties had their maximum yield where 90kgha^-1 was applied. Faro 15 at the application of 90kgha^-1 had higher values than nil application and these values were significantly (p<0.05) higher than values obtained from either the application of 60kgha^-1 or that of 120kgha^-1 under the same experimental conditions. These results are discussed in light of nitrogen fertilizer effect on the growth and yield of rice.