Hepatocellular carcinoma (HCC) is nowadays the sixth cause of tumour-related deceases worldwide, estimated to become the third in Western countries by 2030. New drugs for HCC treatment still have many adverse efects. Several lines of evidence indicate that plant metabolites ofer concrete opportunities for developing new therapeutic strategies for many diseases, including cancer. We previously reported that ethyl acetate extract of a spontaneous edible plant harvested in Apulia, Crithmum maritimum, signifcantly inhibited cell growth in HCC cells. By 1 H-NMR spectroscopy, here we show that Crithmum maritimum ethyl acetate extract counteracts the Warburg efect, by reducing intracellular lactate, inhibits protein anabolism, by decreasing amino acid level, and afects membrane biosynthesis by lowering choline and phosphocholine. Also, we observed an efect on lipid homeostasis, with a reduction in triglycerides, cholesterol, monounsaturated fatty acids (MUFA), and diunsaturated fatty acids (DUFA), and an increase in polyunsaturated fatty acids (PUFA). Taken together, these data demonstrate that Crithmum maritimum-induced cytostasis is exerted through a multi-efect action, targeting key metabolic processes in HCC cells. Overall, our fndings highlight the role of Crithmum maritimum as a promising tool for the prevention and the improvement of the therapeutic options for HCC and other types of tumours.