Ageratum conyzoïdes (Aerial part) is a medicinal plant commonly used in traditional medicine in Côte d’Ivoire in the treatment of various diseases including bleeding. The objevctives of this study were investigated the hemostatic effects of A. conyzoïdes aqueous aerial part extract at differents volume in vitro, using blood samples from apparently healthy human volunteers. Its properties have been identified by hematologic tests such as coagulation time, prothrombin and activated cephalin time. The results showed that the aqueous extract of A. conyzoïdes (100 mg/mL) significantly (p < 0.001) reduced clotting time, prothrobin time, and activated cephalin time compared to the control (administered with only NaCl 0.9 %) in the blood obtained from the volunteers. In contrast, the aqueous extract did not influence thrombocytes count (p > 0.05). The aqueous leaf extract of A. conyzoïdes in a volume of 0.5 mL in this study had coagulation properties, which indicates the positive hemostatic effect on in vitro method. In cconclusion, this study justifies its use to traditionally stop bleeding.