The classic oral manifestations of vitamin B(12) deficiency are considered nonspecific. We describe 4 patients with oral linear lesions associated with vitamin B(12) deficiency. Patients were free of neurologic symptoms and anemia at diagnosis. We believe that glossitis with linear lesions is an early clinical sign of vitamin B(12) deficiency. We recommend the determination of vitamin B(12) in such patients, even in the absence of anemia.