When people look online for information about humanitarian crises, they increasingly encounter media content that blurs the line between reality and fiction. This includes everything from rumour and exaggeration to partisan journalism and completely invented stories designed to look like real news (so-called ‘fake news’). This article shows that disinformation is causing real and serious harm to those affected by humanitarian emergencies; it can undermine the ability of humanitarian workers to provide relief; and it has exacerbated conflict and violence. Disinformation is also making it harder for journalists to report on the humanitarian sector, and hold the powerful to account, because it undermines audience trust in information more generally. The article concludes by considering interventions that could address the challenges of disinformation. It argues for more support of quality journalism about humanitarian crises, as well as media literacy training. Finally, it is crucial that aid agencies and news outlets commit to accuracy and fact checking in their reporting and campaigning.