The disorders of sex development can occur in different domestic animals, but they are not very common. They are classified as sex chromosomic disorders, gonadal sex development disorders andphenotypic sex disorders and have different subcategories. The aim of this study was to describe the phenotypic, chromosomal and anatomical traits of the reproductive organs of a canine patient 3-year-old, apparently female with disorder of sexual development, which presented a protuberance into the vagina with bleeding andpus, which anamnesis male behavior report. A general examination was performed by systems, ventral abdominal ultrasound,latero-lateral radiography, blood count and karyotype whit R-replicative bands. After the evaluation found an enlarged clitoris (pseudopene) with urethral opening that showed resistance to placing a catheter. Radiography showed a structure similar to penis bone and the ultrasonography a structure consistent with the cervix in a female and a structure similar to gonadal tissue in the side. The karyotype was typical of a male, compatible with a male pseudo-hermaphrodite, which classifies the individual as XY with a phenotypic disorder of sex development (78, XY) according to the new classification. With the diagnostic tools found in Colombia is possible to make an appropriate differential diagnosis. But nevertheless, lack of availability of specific diagnostic tests such as FISH and serological measurements.