Study and use of plants as a medicine has a great record in many traditional system of medicine in different part of the globe. Annona muricta of Annonaceae family, posses many medicinal properties and used for treatment of various diseases. In this study, detailed pharmacognosy evaluations of seeds of Annona muricata were carried out, Anti-oxidant activity of different extracts determined and bio-assay guided fractionation approach used for in-vitro anti-cancer screening of seed on human cancer cell lines by using Sulforhodamine B (SRB) colorimetric cytotoxicity assay. The result showed important Pharmacognostical characteristic of seeds of Annona muricata, the phytochemical screening gave a positive test for presence of various phytoconstituents. Anti-oxidant tests showed the anti-oxidant capacity of each extracts in connection with other extracts and standard drug. In addition, bio-assay guided fractionation lead to collect different extracts and fractions which compared with the known standard drug of Adriamycin (Doxorubicin), and showed significant activity against tested human cancer cell lines with GI50 <10 μg/ml which demonstrate very promising effect. On conclusion, the Annona muricata seeds with unique pharmacognostical characteristics showed important biological activity, which prove its medicinal value and its potency as an important medicinal plant for drug discovery process from natural products.