Aim: Jatropha gossypifolia belongs to the family “Euphorbiacea”. The coagulant activity and the mechanism of action of Jatropha gossypifolia stem latex as a haemostatic agent were investigated. Methods: The mechanism of action was investigated using doubling dilution technique by mixing neat (undiluted) and serial dilutions of the latex with 30% bovine albumin. Results: The results of whole blood clotting time using Lee and White method and bleeding time using Ivy’s method were significantly reduced (P < 0.05) when stem latex was introduced than when the tests were performed without stem latex. This means that the stem latex possesses procoagulant activity. Conclusion: The result of this test showed that precipitation of coagulant factors is the mechanism of action of its haemostatic activity.