Online self-diagnosis, where consumers engage with technology by applying their knowledge and skills to generate a medical diagnosis without the participation of a health care professional, is commonplace. Although co-creation of value for consumers and e-health service providers (i.e., suppliers of technological interfaces for consumers to self-diagnose) can occur via “do-it-yourself” diagnosis, we argue that it also has strong potential for value co-destruction. This is because of deficiencies in or misuse of resources (consumer or e-health provider). Based on a review of the service science, information systems and health care literatures, we develop a typology of value co-destruction in online self-diagnosis. It shows that online self-diagnosis can result in value co-destruction of consumers' service process and outcome when consumer resources are deficient or misused (e.g., knowledge) or when e-health provider resources are lacking (e.g., poor quality offerings). The value co-destruction perspective has not been examined previously in this context and is important because it can negatively affect consumers' well-being. A consumer and service focus is missing from research on online self-diagnosis, which our typology addresses. Implications of our typology for providing online health information and more specialised self-diagnosis services are discussed, drawing on a multi-pronged, multi-stakeholder approach, along with future research opportunities.