Nowadays herbal medicine presents a significant adjuvant tool for hard treatment, especially in the case of cancer where modern medicine has access to traditional medicine to deprive the patient of the side effects of therapeutic approaches such as surgery and chemotherapy. Thus, Lebanese 10452 km 2 are so rich in medicinal plants such as Eryngium creticum L. and Euphorbia macroclada Boiss that are traditionally used in the treatment of various diseases (leukemia, asthma, skin diseases, antidote to snake venom, tumors, etc.). To fully realize the importance of these two Lebanese plants, we tried at first to study the phytochemistry of three extracts (aqueous, methanolic and ethyl acetate) from fresh leaves and stems of both plants. In a second step, the antioxidant capacity of these three extracts from the two parts of the fresh plants using spectrophotometric analysis has been evaluated and their cytotoxicity on the MCF7 breast cancer cell line by the XTT Cell viability technique has been studied. Our results showed that both leaves and stems of these two plants contain alkaloid, tannin, coumarin, saponin, flavonoid, polyphenol and reducing sugars in different concentrations. Moreover, both leaves and stems have exerted an antioxidant activity that may be due to their phenolic content and they have also inhibited the growth of cancer cell line from 68 % to 72 %. These results showed that both plants can be considered as a good source of natural products that can be used in the prevention of several diseases.