Symptomatic hemorrhagic transformation is common in supratentorial and cerebellar infarction, but is rare in brainstem infarction. It is seldom reported in basilar artery occlusion. Although early arterial recanalization by thrombolytic agent has became the new trend of treatment, for some neurologists anticoagulant is still a conventional alternative treatment of basilar artery occlusion, especially in longer-existing ischemic deficits. We report a case of massive pontine hemorrhage associated with enoxaparin (low-molecular-weight heparin) treatment for basilar artery occlusion. On the basis of the clinical information and neuroimaging, an embolism was the most likely cause of stroke. The case presented herein adds massive pontine hemorrhagic transformation to the list of possible complications of anticoagulants for basilar artery occlusion. Apart from no evidence-based benefit in treatment of basilar artery occlusion, anticoagulant may contribute to devastating hemorrhagic transformation.