Introduction Hong Kong has one of the lowest rates of deceased organ donation (OD) in the world.1 In a Hong Kong survey in 2019, only 31.7% of the general population were willing to donate organs.2 In Hong Kong, consent of the next-of-kin (eg spouse/child/parent/sibling) is required for OD of deceased persons regardless of the deceased person’s decision. However, 76.6% of the general population were unaware of their family members’ wish on posthumous OD.2 Therefore, communication with family members about OD is as important as registration. We developed a multicomponent intervention (by integrating e-health strategies and motivational interviewing3 ) and evaluated its efficacy in facilitating expression of OD wish to family members. In addition, we explored potential mediation effects of self-efficacy and perceived barriers/facilitators in expression of OD wish to family members.