Purpose: Social contact is known to be vital for older adults' mental and physical health but, because communication impairments often co-occur with other types of disability, it is difficult to generalize about the relative impact of a communication impairment on the social relationships of older adults. Specific aims of the study were to examine whether the severity of a communication impairment was associated with a range of social measures and to examine the association between these characteristics and psychological well-being. Method: Community-dwelling older adults ranging in age from 65 to 94 were recruited for the study of Communication, Health, Aging, Relationship Types and Support. The sample included 240 participants with communication disorders arising from a variety of etiologies including hearing impairment, voice disorders, head and neck cancer, and neurologic disease, as well as older adults without a communication disorder. Results: Communication impairment was a significant independent predictor for key characteristics of social relationships, including the number of friends in the social network, two types of social support, the frequency of social participation, and social self-efficacy. Communication impairment was also a significant predictor for higher levels of loneliness and depression. In addition, two distinct pathways between communication impairment and psychological well-being were identified, with social self-efficacy and reassurance of worth as mediators. Conclusions: Even after controlling for age, gender, health, and disability, communication impairment is a significant independent predictor for key aspects of the social function of older adults and demonstrates two distinct pathways to loneliness and depression.