The incubation of primary leaves or immature zygotic embryos of cowpea in culture media containing auxin, leads to the induction of friable embryogenic callus (FEC). These FEC are able to differentiate into somatic embryos (SE) that in turn germinate into mature plants. However, the frequency of conversion of FEC into SE is so low as to preclude its use as target for genetic transformation. In order to understand the causes underlying this low conversion rate, we set out to identify the proteins present in embryogenic cell suspension (ECS) prepared from FEC, so that we could make a comparison with those present at the early stages of zygotic embryogenesis. The proteins in ESC were analyzed by 2D-gel electrophoresis and selected spots were excised from the gel, digested with trypsin and analyzed by MS/MS for protein identification. The two most abundant proteins were identified as a PR-4 (chitinase) and as a PR-10 (ribonuclease) by their similarities with the proteins coded by 2 cDNAs from Vigna unguiculata (accession numbers AAG23965 and T11670, respectively). Primers spanning the 5’ and 3’ regions of these cDNAs were designed and used in RT-PCR experiments to confirm the expression of the PR-4 and PR-10 genes in ESC and in other tissues such as leaves, roots and stems under control and stress conditions. These same primers were used to isolate cognate cDNAs from the ESC and their identities were confirmed by sequencing. A synthetic peptide 15 amino acids long, corresponding to the C-terminal region of the PR-10 protein was synthesized and used for the production of polyclonal antibodies in rabbits. These antibodies cross-reacted with proteins having a MW of 17.2 KDa present in the ESC and in developing seeds, flowers, stems and roots, confirming the expression pattern that was unraveled in the RT-PCR experiments. The physiological significance of the presence in high concentration of these two PR proteins in ESC is now under investigation.