There is a high prevalence of dysphagia among patients with neuromuscular diseases and cerebrovascular diseases, and its consequences can be profound. However, the correlation between dysarthria and oral-oropharyngeal dysphagia remains unclear. We conducted a literature review to define the clinical presentation of both dysarthria and dysphagia in patients with neuromuscular and cerebrovascular diseases. We performed a systematic PubMed search of the English-language literature since 1995. Objective and subjective outcomes instruments were identified for both dysarthria and dysphagia. Studies that included the incidence of concomitant presentations were included. Inclusion and exclusion criteria were applied according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Of the 1,056 articles we reviewed, we selected 24 for analysis. We found that dysarthria and dysphagia were common among patients with neuromuscular and cerebrovascular diseases. Overall, there was a higher prevalence of dysarthria than dysphagia. Of those patients with dysphagia, some reports found that 76 to 90% of patients with neuromuscular disease also had dysarthria. Dysarthria is a strong clinical clue to the presence of dysphagia. Existing subjective questionnaires may not reveal the presence of oropharyngeal dysphagia; objective measures are obviously more revealing. Further studies to correlate the degree of dysarthria and the severity of oral-oropharyngeal dysphagia are warranted.