Background <p>Cognitive impairment poses a major public health concern in ageing societies. This study investigated the independent and joint associations of resilience and social support with cognitive function among community-dwelling middle-aged and older Chinese adults, and explored gender-specific differences.</p> Methods <p>A total of 3,058 Chinese adults aged ≥ 50 years from both urban and rural communities were included. Cognitive function was evaluated using the Mini-Mental State Examination (MMSE). Resilience was assessed using the 10-item Connor-Davidson Resilience Scale (CD-RISC-10), and social support by the 6-item Lubben Social Network Scale (LSNS-6). Logistic regression models stratified by gender were applied with adjustment for demographic, behavioral, and health-related variables. Generalized additive models were used to test non-linear associations, and joint effects were examined with combined categories.</p> Results <p>Overall, 18.4% of participants (20.1% women, 16.3% men) had cognitive impairment. Higher resilience and social support were independently associated with lower odds of cognitive impairment, with some variation in effect strength across sex, age group, and educational attainment in sensitivity and stratified analyses. Curvilinear associations were observed in generalized additive models. Compared with low resilience and low support, participants with moderate resilience and high support had the lowest risk (OR = 0.25, 95% CI: 0.11–0.51).</p> Conclusions <p>Resilience and social support were independently and jointly associated with cognitive function among middle-aged and older adults. These associations appeared to be stronger in women, although variation by sex was observed. Given the cross-sectional design, the findings should be interpreted as exploratory, and further longitudinal and interventional studies are needed to clarify the role of psychosocial resources in cognitive ageing.</p>