Objective: A meta-analysis was performed to assess the association between asthma and dementia, aimed to provide initial exploration for further etiolotical/preventive/clinical discussion. Methods: A systematic search of Pubmed, Embase, Web of Science and Cochrane library databases was conducted to screening evidence. Cohort/case control studies that are focused on the association between asthma and the onset of dementia were identified in the current meta-analysis. The search time frame was from database establishment to August, 1st, 2023, with independent reviewers screening the literature. The quality of the literature was evaluated by Newcastle-Ottawa Quality Assessment Scale (NOS). R 4.3.2 was used in data analysis. Results: 9 studies including 234248 participants were included. The overall quality of the included studies was high, with an average NOS score of over 8. The results of the meta-analysis in the current study confirmed that there is an association between asthma and cognitive dysfunction. It is noteworthy that the significant association was found between all-severity levels-of-asthma and the risk of onset of all-types-of-dementia when we define it as dichotomous variable. Moreover, subgroup analysis revealed a high risk of dementia in specific asthma patients. Conclusion: Our findings showed a significant increase in the risk of dementia among patients with asthma, and this risk is not affected by the types of dementia, however it seems especially obviously among specific asthma patients.