The aims of this work was realised the morphological study of the female external genitalia of Myocastor coypus. The vulva was rudimentary and limited by two folds scarcely developed. Its external surface showed a cover with scarce and long hairs while the internal surface had a hairy cover and no pigmentation. The lining of the vulvar area showed a squamous stratified epithelium resting on a lamina propria with many microscopic papillae. In the lamina propria there were abundant small glands of sebaceous aspect associated to pilose follicles of small diameter. The clitoris was a prominent conic structure, with a small glans covered by the prepuce of the clitoris. The prepuce, of rugose surface and soft and flexible consistency, projected point-first towards ventral. The clitoris had a well-developed cavernous body (corpus cavernosum), with muscular tissue in the basal zone, formed the body of the clitoris. The axial part of the body had an elongated hyaline cartilaginous nucleus. The urethral opening was observed as a longitudinal fissure at dorsal of the clitoris, behind the glans