Cowpea is a new potential crop in the Delmarva Peninsula region of the United States. Information on the symbiotic response of cowpea genotypes to Bradyrhizobium inoculation is lacking in this region. Therefore, a field study was conducted to investigate the effect of Bradyrhizobium spp. application on nodulation, growth and grain and biological yields of twenty two cowpea genotypes. Cowpea seed were surface sterilized and inoculated with a mixture of three Bradyrhizobium spp. at the time of planting. Most cowpea genotypes provided higher seed yield and biological yield and had higher number of nodules when seeds were inoculated with bradyrhizobia inoculants. Results showed a significant overall increase in seed yield of cowpea genotypes which had received Bradyrhizobium treatments. Also, there was about 25% increase in most of the biological yields of the inoculated cowpea genotypes over the uninoculated genotypes. It is concluded from this study that the use of Bradyrhizobium inoculants could play a significant role in enhancing cowpea growth and yield in the Delmarva region of the United States.