Posterior drooling, which can lead to substantial respiratory morbidity, including unexplained lung diseases and recurrent pneumonia, is an important issue in the rehabilitation unit. There are various treatment options for posterior drooling, including pharmacologic therapy, oral motor or behavioral therapy, biofeedback, local glandular injection of botulinum toxin, irradiation, and surgery. Among them, nebulized glycopyrrolate has the following advantages: It is noninvasive and is relatively free of central adverse effects because it does not cross the blood-brain barrier unlike other anticholinergics. Although there has been one case report regarding the effectiveness of nebulized glycopyrrolate for drooling in a motor neuron patient, there have not been any reports on its effectiveness for posterior drooling. Herein, we report two cases (an 82-year-old male bilateral hemiplegic stroke patient and a 1-year-old female cerebral palsy infant with bilaterally spastic hemiplegia of posterior drooling treated with nebulized glycopyrrolate) and identify salivary aspiration and the effect of nebulized glycopyrrolate using radionuclide salivagram. Considering its advantages and effectiveness, nebulized glycopyrrolate should be considered as one of the reliable methods to manage posterior drooling in patients with impaired cognition or swallowing difficulties, such as severe brain injury.