This study attempts to evaluate the biochemical composition and some in vitro biological activities of a spontaneous plant; Fumaria officinalis growing in a Tunisian arid region. Leaf extracts were obtained using two extraction methods and solvents of varying polarities. The biochemical analysis enclosed quantifying polyphenols, tannins, and flavonoids besides the extraction of alkaloids. Concerning its in vitro biological activities, the antioxidant potential was assessed using three testes, where the ethanol maceration extract demonstrated the highest effectiveness. Besides, the evaluation of the anti-inflammatory activity revealed moderate efficacy in both aqueous and ethanol maceration extracts. The antidiabetic assessment indicated that the aqueous maceration extract exhibited the strongest activity. Furthermore, the antiproliferative activity results disclosed a significant inhibition of breast cancer cell proliferation. Eventually, the antibacterial activity against both Gram positive and negative bacteria, confirmed that Fumaria officinalis has a limited efficacy. This research highlights the potential of Fumaria officinalis leaves collected from Southern Tunisia, for its diverse applications, particularly within healthcare and pharmacology the fields, by shedding light on the multifaceted attributes of its extracts.