To contribute to the development of local medicinal plants for their therapeutic properties, we are interested in the study of Citrullus Colocynthis plant known in traditional medicine. The Citrullus Colocynthis is a desert plant encountered on sandy soils in the region of Ghardaia and also very well known for its medicinal virtues. In the present work we have characterized the seed oil of the plant with a yield of 17,854%, for the determination of different chemical indicators such as the acid value (AV), iodine (II), of saponification (IS), peroxide (IP) and physical indicia as the refractive index (RI) and the density. The result shows that this oil is rich in fatty acids such as palmitic acid (C16) and stearic (C18). The defatted seed contain a very large amount of proteins studied by three methods: Biuret, Lowry and Kjeldahl method.