Clinical signs, blood parameters, postmortem and histopathological findings in sheep that were accidentally poisoned with Catharanthus roseus are described. Affected animals (40 sheep) showed acute clinical signs such as salivation, dyspnea, anorexia, bloody diarrhea and dehydration. Blood samples were collected from 5 sheep prior to death. Marked increase in Activated Partial Thromboplastin Time (APTT), D-DIMER, hemoglobin, urea and creatinine levels with the decrease in cholinesterase activity and calcium levels were observed in the blood parameters of affected sheep. Necropsy examination was performed in 17 sheep and all organs were examined pathologically. According to blood parameters and pathologic findings, Disseminated Intravascular Coagulation (DIC) was observed in different organs supported by the increases in APTT, Prothrombin time (PT) and D-dimer levels in blood. Grossly, linear mucosal hemorrhages in the jejunum and ileum, auricular petechial hemorrhages in the heart were common findings. The livers were pale and friable. Microscopically, the fibrinous exudate consisting of fibrin networks were seen in the lumen of jejunum and ileum. In addition, clumps of fibrin in many small vessels were noted in the brain, lungs, liver, kidneys and intestines. Focal periacinar and mid-zonal necrosis with hemorrhages were observed in the liver. Marked tubular necrosis was seen in the kidneys.