Objective To study the effects of diallyl sulfide (DAS), an organosulfur compoundpresent in garlic (Allium sativum), on the life span of ehrlich ascites (EA) tumor bearingSwiss albino mice, cytotoxicity and angiogenesis. Methods EA tumor cells weremaintained by serial transplantation in peritoneal cavity of male Swiss albino mice. EAtumor cells were inoculated at concentrations of 1× 106 EA cells, 2.5× 106 EA cells and5× 106 EA cells. DAS was given in 0.2 ml normal saline i. p., daily for seven days followedone hour later by inoculation with EA cells in respective groups. Results The resultsrevealed that administration of DAS increased the life span of EA tumor bearing animals bymore than 25 percent. A significant dose dependant cytotoxic response of DAS was alsoobserved on EA tumor cells. DAS was also found to inhibit the angiogenesis in EA tumorbearing mice in a dose dependent manner. Conclusion It is suggested that DAS may exertits anticarcinogenic effects by more than one mechanism and is a useful chemopreventiveand chemotherapeutic agent. Objective To study the effects of diallyl sulfide (DAS), an organosulfur compound present in garlic (Allium sativum), on the life span of ehrlich ascites (EA) tumor bearing Swis albino mice, cytotoxicity and angiogenesis. Methods EA tumor cells were master staged by serial transplantation in EAtumor cells were inoculated at a concentration of 1 × 10 6 EA cells, 2.5 × 10 6 EA cells and 5 × 10 6 EA cells. DAS was given in 0.2 ml normal saline ip, daily for seven days followedoneone hour later by Results The results was results of administration of DAS increased the life span of EA tumor-bearing animals by more than 25 percent. A significant dose dependent cytotoxic response of DAS was alsoobserved on EA tumor cells. DAS was also found to inhibit the angiogenesis in EA tumorbearing mice in a dose dependent manner. Conclusion It is suggested that DAS may exert anticarcinogenic effects by more th an one mechanism and is a useful chemopreventive and chemotherapeutic agent.