The present research was carried out to record and report the ecological, taxonomical, anatomical and ethno botanical properties of 36 wild medicinal xeric plants of district Bannu. In the present research we evaluate the biological activities of few selected xeric plants. i.e. Calligonum polygonoides (L.), Rosa brunonii, Pegnum harmala (L.) and Sueda fruticosa. The present investigation comprises of nature (habit), soil type and atmospheric conditions in which the plant grow (habitat); adaptation which may be physical, physiological or anatomical, particularly stem anatomy. We reported taxonomical characters for identification and local uses of 36 plants species which belonging to 22 families of angiosperm. Based upon their utility all the studied plants are wild medicinal xerophytes maintain balancing in ecosystem and also protect the xeric environment from erosion, desertification and provide natural habitat to wild fauna. The anatomical study of all the mentioned plants was undertaken in herbarium of Botany University of Science and Technology Bannu and herbarium of Quid-eAzam University Islamabad. It was investigated that all the mentioned species of xerophytes have well developed cuticle, epidermis, trichomes, more number of simple tissue (parenchyma, collenchyma and sclernchyma cells), cortex and vascular bundles in stem systems which clarified their adaptation in the severe drought conditions i.e. xeric area of district Bannu, Khyber Pakhtunkhwa, Pakistan. Ethno botanical study shows that all of the mentioned plants were used as a fuel. Beside these, eleven species used as fodder for cattle and eight species found useful as timber. Similarly, some species have edible fruit such as Zizyphus mauratiana (L.), Acacia modesta (L.) wild, Salvador oleoides (L.), six xeric plants were found as honey bee species, eight species were found useful for agricultural tools and six species were found to be cultivated. The most important families having medicinal values were Amaranthaceae having three plant, Apocynaceae having one plant, Asclepiadaceae have two plants, Capparidaceae having one plant, Chenopodiaceae having two plants, Cucurbitaceae having one plant, Cuscutaceae has one plant, Elaeagnaceae has one plant, while Euphorbiaceae have two plants, Mimosaceae have four plants, Papilionaceae have one plant, Polygonaceae having one plant, Rhamnaceae have two plants, Rosaceae having 2 Plants, Salvadoraceae having one plant, Solanaceae having 3 plants, Tamaricaceae having one plant while Verbenaceae has one plant and Zygophyllaceae has also one plant. The most common wild medicinal plants in district Bannu were Calotropis procera, Solanum surratense, Ricinus communis (L.) Nerium odorum, Vitex negundo. Some plants have wild fruit such as Capparis decidua, Salvadora oleoides. Famous fodder species of the area were Acacia modesta, Acacia nilotica (L.) and Zizyphus nummularia (L.). Few wild medicinal plants have best biological activities such as Calligonum polygonoides, Rosa brunonii, Pegnum harmala and Sueda fruticosa. All of the selected plants have phytotoxic activities while the antibacterial activities were high in the first three plants, the Sueda fruticosa which is a halophyte have less antibacterial activities, similarly antifungal activities were strong in Calligonum polygonoides, Rosa brunonii and Pegnum harmala but poor in Sueda fruticosa, the cytotoxic activities were found strong in Calligonum polygonoides, Rosa brunonii but moderate in Pegnum harmala and poor in Sueda fruticosa. It can be concluded that, xerophytes convert the desert into cultivated land; xeric plants have best biological activities as compare to other plant groups. It is suggested that vulnerable and over-exploited medicinal plants may be conserved for sustainable use and to protect environment.