A two year field study on the effect of nitrogen and boron fertilization on the growth, nodulation and grain yield of cowpea was carried out fairly widespread boron deficiency has been reported. Treatments consisted of four levels of N (0, 15, 30 and 45 kg/ha) and three levels of B (1, 1.5 and 3.0 kg/ha). Results revealed that higher N level produced maximum biomass per plant, Application of B had no positive effect on the growth parameters. Indeed a decreasing tendency on growth characters was observed with applied B. Application of N and B depressed nodulation. There was no significant interaction effect between N and B on grain yield. Applied N up to 30 kg/ha without B increased grain yield but when applied together, grain yield depression was apparent.