Percutaneous coronary intervention is associated with many complications, and stent thrombosis is the most feared among them. Common etiologies of stent thrombosis include high angiographic thrombus burden, inadequate antiplatelet dosing, total stent length, diabetes, and renal diseases. Rarely, it can be associated with thrombocytosis. We report a rare case of stent thrombosis associated with reactive thrombocytosis. Although acute coronary events have been documented due to essential thrombocytosis, very few cases of reactive thrombocytosis leading to acute coronary syndrome are reported. Thrombocytosis as a possible etiology is suspected when other risk factors including antiplatelet resistance is ruled out. In these cases, adequate treatment of both stent thrombosis and thrombocytosis needs to be administered simultaneously and the possible etiology of thrombocytosis should be sorted out and treated.