The uses of plant medicines are very common in Asia and developing countries. Phytochemicals has been used to treat chronic as well as infectious diseases. Cardiospermum halicacabum Linn. (Sapindaceae) is an herbaceous climber, commonly found throughout India, used as vegetable as well as traditional medicine for rheumatism, lumbago and nervous diseases. Many pharmacological studies have been done with various parts of C. halicacabum plant to demonstrate its medicinal effect. The present work was aimed to isolate the active compounds from the leaf extract of C. halicacabum. The hydro alcoholic leaf extract (80% methanol + 20% distilled water) was subjected to isolation procedures for identification of active compounds. Eleven compounds were got and in vitro anti oxidant analysis were done with the isolated compounds. Compound 1 and 8 selected for structural elucidation. The NMR spectrum showed characteristic peaks of compound 1 and 8 and the active phytoconstituents were identified as Kaempferol- 3- o- alpha- l- rhamnoside and Apigenin - 7- o- beta - d- glucuronide by structural elucidation. The isolated compounds showed strong antioxidant potential.