Bevacizumab, which is a humanized monoclonal antibody against vascular endothelial growth factor, is used to treat metastatic cancers of the colon. Adverse effects common with bevacizumab treatment are hypertension, arterial-venous thrombosis, bleeding, gastrointestinal perforation, and proteinuria. To date, there have been no reports of refractory seizure following treatment with bevacizumab. We describe a patient who presented with refractory generalized tonic-clonic seizures after receiving last dose of bevacizumab for treatment of metastatic colorectal cancer with FOLFIRI and bevacizumab regimen.