Anti-fatness, the systematic marginalization of fat bodies, is a pervasive attitude across all spheres of social work practice. Despite its prevalence, there is a notable lack of understanding about anti-fatness, its causes, and its consequences. We argue for the need to address the issue of anti-fatness in the curriculum of social work education to better prepare social workers to serve all clients, as well as to serve as advocates against anti-fatness and the policies and conditions that emerge from it.