ABSTRACT. There is an increasing number of aged people who provide care for other older people. Commonly existing burden and stress can change the forms of cognitive performance depending on the context of the aged caregivers. Objective: To compare the cognitive performance, burden and stress of aged caregivers of older adults with and without signs of cognitive impairment. Methods: A cross-sectional and quantitative study conducted with 205 aged caregivers of older adults with signs of cognitive impairment and 113 aged caregivers of older adults without signs of cognitive impairment treated in Primary Health Care. They were evaluated for sociodemographic characteristics, cognition, burden, and stress. Descriptive (Kolmogorov-Smirnov test) and comparative (Student's t-test and Pearson's χ² test) analyses were performed. Results: Aged caregivers of older adults with signs of cognitive impairment were older, had lower schooling levels, and a higher percentage of daily care hours compared to the aged caregivers of older adults without signs of cognitive impairment. Regarding cognitive performance, the means were lower for all domains. In addition, this same group had higher scores, with a statistically significant difference for perceived stress and burden. Conclusion: Aged caregivers of older adults with signs of cognitive impairment showed lower cognitive performance, as well as higher burden and stress levels. These findings guide the planning of interventions with aged caregivers in the Primary Health Care.