The present study investigates the chemical composition of essential oil of leaves of Tridax procumbens (L.) and its invitro anticancer activity.  Traditionally, the plant is used for malaria, stomachache, high blood pressure, hemorrhage and to prevent hair fall as well. It possesses antifungal, antibacterial, antiseptic, insecticidal, parasiticidal and hepatoprotective properties. The hydrodistilled essential oil of T.procumbens contains total of 18 components by GC-MS analysis. Dibutyl phthalate (19.29%), Trans-(α)-caryophyllene (9.55%), Biformeme (3.95%), p-cymen-7-ol (2.52%), 1,8-cineole (2.44%). And the minor compounds are trans-α- Bergamotol (1.78%), 2-α-pinene (1.62%), α-Selinine (1.49%), Caryophyllene oxide (1.39%), α-humulene (0.95%),  The obtained essential oil was tested against Human breast cancer cell line (MCF-7) for its anticancer activity by MTT assay with different concentrations of essential oil (18.5-300 µg/ml). The result revealed that the essential oil showed concentration dependent activity against cell line. The IC50 value of MCF-7cell line was 96.6 µg/ml. This may be due to the presence of important terpenes present in the oil. There are only few reports are available for anticancer activity efficacy of this plant. Our findings confirm the anticancer potential of the T.procumbens.