Self-harm-related posts on social media are a growing public health concern. To address the high rate of self-harm posts on their platform, Instagram introduced (in 2016) a tool for users to anonymously report posts that suggest engagement in, or support for, self-harm. Grounded in diffusion of innovation and the theory of planned behavior, the purpose of this study was to evaluate awareness of, and intention to use, the self-harm reporting tool among Instagram users. Survey data collected from 417 undergraduate Instagram users suggests that users are generally unaware that the self-harm reporting feature exists within the platform. However, once informed that the tool is available, regression analysis found attitudes, subjective norms, and perceived behavioral control to predict high intention to use the tool as a method for addressing risks of self-harm. Implications from these findings extend theoretical understandings of social media-based health behavior as well as practical recommendations for reducing risks of self-harm on social media platforms.