Purpose: The aim of this study was to investigate and compare family caregivers’ and nurses’ perceptions of the adult guardianship system applied to people with dementia. Methods: The participants were 85 family caregivers and 85 nurses in a university hospital and a dementia support center in S city. The perception of the adult guardianship system was surveyed using a structured questionnaire. Data were analyzed using descriptive statistics, chi-squared test, and Fisher’s exact test with the SPSS/WIN 24.0. Results: Twenty-eight percent of nurses said they had heard of the adult guardianship system and fifty-one percent of family caregivers said they had heard of it (x2=9.80, p=.002). Perception of system details was also higher among family caregivers. However, both groups were less aware of the details. In the case of nurses, perceptions of the system differed according to factors related to education. Conclusion: Family caregivers were more likely to recognize the adult guardianship system than nurses. However, their awareness of the system details was low. Given that the application of the adult guardianship system will become more dynamic, it is necessary to actively promote and provide education about the system. Specifically, dispensing instruction for the system is necessary for nurses.