<p style="text-align: justify;">The research aimed to evaluate the effect of online social support (OSS) on the psychological well-being (PWB) of caregivers of children with autism spectrum disorder (ASD). The role of gender as a moderator variable in the relationship between online social support to psychological well-being also was assessed. A quantitative research design was used to collect data using questionnaires of PWB and OSS adapted into Bahasa given to 154 caregivers of children with ASD who live in Indonesia. Data were analyzed using SMART PLS 3.0. Online social support affects the psychological well-being of caregivers of children with ASD. At the dimension level, some dimensions of OSS also influence PWB. There was no difference in the effect of online social support on psychological well-being in the male and female groups, meaning that online social support had the same effect on psychological well-being in the male and female groups. The following study is suggested to combine the study with a qualitative method to gain data from caregivers on how OSS impact their PWB, so a holistic viewpoint is gained. It can be a suggestion to policymakers to provide beneficial online social media for caregivers of children with ASD.</p>