Coagulopathy in cats (Felis catus) parasitized by Trypanosoma evansi in both the initial and chronic phases of the disease has been investigated. To address this issue, seven animals were infected with 108 trypomastigote forms each, and six were used as control. Animals were monitored for 56 days by examining daily blood smears. Blood samples for hematocrit, platelet counting, and fibrinogen levels were collect at 15-day intervals. Prothrombin time, activated partial thromboplastin time, and number of megakaryocytes were analyzed at days 14 and 42 post-inoculation. A decrease in hematocrit values and platelet counts and an increase in plasmatic fibrinogen concentration were observed in the infected cats (P < 0.05). Coagulation time did not differ between the infected and non-infected groups. The reduction in platelet count increased the number of megakaryocytes in the infected group (P < 0.05). These results indicate that the infection by T. evansi in cats increased the number of megakaryocytes in response to primary clotting disorders.