Products of plant mevalonate metabolism, like geraniol (GOH), have multiple pharmacologic effects on animal mevalonate metabolism; some of them may account for their effects on some tumor cells. To investigate the impact of dietary geraniol on lipid metabolism and growth of tumor cells “in-vivo”, we implanted A549 cell line in nude mice. Animals were fed a control or experimental (25; 50 or 75 mmol.GOH/kg diet) diet for 25 days after tumor implant. Tumors were measured and animals were weighed twice a week. On day 25 mice were killed and livers, blood and tumors were removed. Three hours before sacrifice, animals were injected with 25 µCi de 14C-acetate. Cholesterolemia, incorporation of radioactivity into liver and tumor lipids, HMGCoA reductase and SREBP2 were determined. Higher doses of GOH significantly reduced tumor growth but only the highest dose significantly reduced mice body weight. Serum cholesterol diminished in GOH treated host mice (12±1.5%) and non-host mice (7±1.5%). GOH decreased 14C-acetate incorporated into total and nonsaponifiable lipids in liver and tumor of treated mice, and reduced HMGCoA reductase levels (23.9±1.9%) and SREBP2 levels (24.1±2%) in non-host mice liver. Host mice SREBP2 level was only reduced with the highest GOH dose. We concluded that geraniol inhibited tumor growth, diminished serum cholesterol and modified tumor and liver lipid metabolism.