Background and objectives: Family caregivers of people with dementia experience high burden making medical decisions for their loved ones. Undertaking Advance Care Planning (ACP) can help reduce burden and stress. Having experiences making medical decisions for someone else may influence the way people make decisions for themselves. Therefore the aim of this study was to assess the willingness of family caregivers of people with dementia to undertake ACP for themselves, using the Theory of Planned Behavior. Research design and methods: Face-to-face interviews were conducted with 195 family caregivers of people with dementia. A structured questionnaire was used to assessed participants' attitudes, subjective norms, perceived control, anticipated regret, the wish to prolong life and caregiver burden. Hierarchical regression analysis was performed to test the contribution of the variables to the willingness to undertake ACP. Results: Overall, participants expressed moderate willingness to undertake ACP. Among the various options for undertaking ACP, the highest willingness expressed was to appoint a durable power of attorney and the lowest willingness was to have informal conversations with their doctor. The hierarchical regression revealed that attitudes, subjective norms and anticipated regrets were main determinants of the willingness to undertake ACP. Discussion and implications: Interventions should be developed to encourage family members to undertake ACP for themselves, which emphasize the advantages of the process and involve significant others in the formal and informal aspects of ACP.