This article considers the impact of internet use and online social capital on the health outcomes of supporters of cancer patients. Structural equation modeling offers support for the following three-step model: internet use online social capital stress and depression. Specifically, asynchronous online communication and offline communication stimulated by online communication had direct positive paths to social interaction and social support which, in turn, were both predictive of healthier or lower levels of stress and depression. These findings support previous research, which has indicated positive associations between mass media use and social capital and between social capital and health outcomes. In contrast, internet information-seeking by information type had a negative direct path to social support and negative indirect paths to stress and depression, indicating that information-seeking online has a detrimental impact on social capital and the health indicators.