Background: Liver cancer is one of the most prevalent and fatal malignancies in the human digestive system, killing over 500,000 people each year worldwide. Aim of the work: This study was to analyze for the first time the phytochemical composition of Atriplex halimus L. by High-Performance Liquid Chromatography technique and to evaluate its anticancer activity on primary cell culture of human liver carcinoma by MTT assay and compared it with a chemotherapy drug. Method: Cancer cells were treated with a concentration of AHE, Cisplatin, and a combination of them. Also, cell viability and morphological changes, Superoxide Dismutase, and Catalase enzyme activity were measured. Results: The results showed two types of flavonols, quercetin, and kaempferol identified. The MTT assay shows the highest cytotoxicity on cancer cells at concentrations of 100 and 200 µg/ml for all treatments. Superoxide dismutase enzyme showed an increased level (P = 0.001) while catalase enzyme showed decreased level (P = 0.032) in treated cells compared to the untreated cell. Conclusion: Our findings suggest that A. halimus possesses antioxidant and anticancer properties, which are possibly due to flavonoids existing in this plant, and could be a potential candidate for the development of drugs for the management of liver cancer cells.