Carotid artery stenosis is an important cause of ischemic stroke. Carotid endarterectomy and carotid artery stenting are the effective methods for treating carotid artery stenosis, but postoperative restenosis remains a challenge. The pathogenesis of postoperative restenosis is currently not fully understood. However, multiple factors, including biomarkers, imaging features, and surgical related factors, have been proven to be associated with postoperative restenosis and can predict the occurrence of postoperative restenosis. This article reviews the predictors of restenosis after carotid endarterectomy and carotid artery stenting.