Background: Renewed interest has recently grown around the relationship between autistic traits (AT) in childhood and adulthood and dementia symptoms in old age. In fact, it seems that individuals with AT are at greater risk of developing cognitive impairment in old age. The aim of this work is to examine, in a group of old individuals, the correlation between AT and cognitive impairment. Methods: In our study we enrolled a group of 122 old individuals (mean age=81.00±7.07 years, M=41, F=81). Participants were assessed for autism spectrum disorder (ASD) symptoms by the Adult Autism Subthreshold Spectrum (AdAS), the Ritvo Autism Asperger Diagnostic Scale-Revised (RAADS), and the Autism Questionnaire (AQ), while for cognitive profile by the Frontal Assessment Battery (FAB), Montreal Cognitive Assessment (MoCA), and Mini Mental State Examination (MMSE). We performed correlation analysis between scores reported in each item of the FAB and MoCA and global scores of the MMSE from one side and the score reported in each item of the AdAS and global scores of the RAADS and the AQ from the other. Results: A positive correlation emerged between the prevalence of AT and better cognitive functions, such as attention, orientation, and executive functions. From the other side, AT in childhood seem to impair subjects’ abilities to attend to conflicting tasks as well as orientation at the MoCA in old age. In addition, ASD non-verbal difficulties impair phonemic fluency and language abilities, respectively, at the FAB and the MoCA. As expected, adherence to routine and inflexibility are associated with difficulties in memory and executive functions of the MoCA as well as impairment in similarities and phonemic fluency at the FAB. Finally, hyperstimulation, typically associated with ASD, negatively affects “language abilities, as assessed by the FAB. Conclusion: Overall, intriguing results were pointed out about the relationship between AT and cognitive functions in old age. Particularly, if AT may preserve some cognitive functions, including attention, orientation, and executive functions from age-related decline, specific features of the disease, such as inflexibility, adherence to routine, and sometimes hyperstimulation may exert a potential negative effect on other aspects such as phonemic fluency, language abilities, conflicting instructions and orientation, and even memory. Further studies are needed to deepen the relationship between AT and cognitive decline in old age.