Here is presented a study of Cenomanian Ostracoda from Tunisia occurring in two different environments. In the Djebel Semmama area, a shelf environment exists, and in the Kalaat Senan area a distal environment is present. In the Cenomanian of the Kalaat Senan area, no distinctive bathyal genus is recognized in this distal setting. Except for two species, the vertical distribution of the most significant ostracodes is generally the same in both environments, so the ostracods can be used as biostratigraphic markers in the two types of environment.