This study explores a nanoemulsion formulated with açaí seed oil, known for its rich fatty acid composition and diverse biological activities. This study aimed to characterise a nanoemulsion formulated with açaí seed oil and explore its cytotoxic effects on HeLa and SiHa cervical cancer cell lines, alongside assessing its antioxidant and toxicity properties both in vitro and in vivo. Extracted from fruits sourced in Brazil, the oil underwent thorough chemical characterization using gas chromatography-mass spectrometry. The resulting nanoemulsion was prepared and evaluated for stability, particle size, and antioxidant properties. The nanoemulsion exhibited translucency, fluidity, and stability post centrifugation and temperature tests, with a droplet size of 238.37, PDI -9.59, pH 7, and turbidity 0.267. In vitro assessments on cervical cancer cell lines revealed antitumour effects, including inhibition of cell proliferation, migration, and colony formation. Toxicity tests conducted in cell cultures and female Swiss mice demonstrated no adverse effects of both açaí seed oil and nanoemulsion. Overall, açaí seed oil, particularly when formulated into a nanoemulsion, presents potential for cancer treatment due to its bioactive properties and safety profile.