To establish a basic strategy for prevention of aspiration pneumonia in patients with motor and intellectual disabilities, we investigated oral opportunistic pathogen (OOP) infections in 31 such patients who were resident at a welfare home. Patients received special oral care from a dental hygienist once a week. OOP samples were collected by scraping the dorsal surface of the tongue, and then cultured. For each patient, the basic reasons for admission and the degree of intellectual disability and mobility were recorded. OOPs were found in 61.3% of the patients, of which methicillin-sensitive Staphylococcus aureus (MSSA) was the most commonly detected (38.7%). A significantly high proportion of male patients were OOP-positive, and a significantly high proportion of patients with mental retardation were Candida sp.-positive. However, multivariate logistic regression revealed that disability was not associated with OOP positivity. No correlation was found between OOP positivity and disability. Nevertheless, special oral care may be beneficial for maintenance of oral health in patients with disabilities.