Achieving rapid and effective hemostasis remains a multidisciplinary challenge. Here, distinctive functional carbon dots derived from carbonized Platycladus orientalis (CPO-CDs) are developed using one-step hydrothermal method. The negatively charged surface of CPO-CDs retains partial functional groups from CPO precursor, exhibiting excellent water solubility and high biocompatibility. Both rat liver injury model and tail amputation model have confirmed the rapid and effective hemostatic performance of CPO-CDs on exogenous hemorrhage. Further, on endogenous blood-heat hemorrhage syndrome rat model, CPO-CDs could inhibit hemorrhage and alleviate inflammation response. Interestingly, the excellent hemostasis performance of CPO-CDs is ascribed to activate exogenous coagulation pathway and common coagulation pathway. More importantly, metabolomics of rat plasma suggests that the hemostasis effect of CPO-CDs is closely related to platelet functions. Therefore, the designed in vitro experiments are performed and it is discovered that CPO-CDs significantly promote platelets adhesion, activation, and aggregation. Further, the underlying mechanism investigation suggests that Src/Syk signal pathway plays a key role in platelets activation triggered by CPO-CDs. Overall, CPO-CDs with rapid and excellent hemostatic performance are discovered for the first time, which could be an excellent candidate for the treatment of hemorrhagic diseases.