Middle-aged and older adults with HIV experience double discrimination and cognitive impairment due to both their HIV status and their age. However, the relationship between perceived discrimination and self-reported cognitive ability in middle-aged and older people living with HIV (PLWH) is less clear. We measured self-reported perceived discrimination and cognitive ability using the Expanded Everyday Discrimination Scale and the subscale of the AIDS Health Assessment Questionnaire (AIDS-HAQ) . The study sample included 324 middle-aged and older PLWH (over 45 years old) from five designated HIV hospitals in three regions (east coast, middle, and southwest regions) of China. The descriptive analysis showed that 45.37% of the participants reported perceiving discrimination at least once in the past twelve months, and 47.22% reported having at least one type of cognitive impairment. Multiple linear regression results showed that higher levels of perceived discrimination (β  = -0.121, P  = 0.036) were significantly associated with lower levels of self-reported cognitive ability after controlling for several covariates, including sociodemographic variables, mental health status, health behaviors, and social support. A longer duration of HIV was also related to a lower level of self-reported cognitive ability. Our findings indicate that perceived discrimination is related to self-reported cognitive ability and suggest that counseling services and support systems should be developed to reduce age- and disease-associated discrimination. A reduction in perceived discrimination would improve not only overall wellbeing but also cognitive ability in later life.