Pathologizing ugliness refers to the use of disease language and medical processes to foster and support the claim that undesirable features are pathological conditions requiring medical or surgical intervention. Primarily situated in cosmetic surgery, the practice appeals to the concept of “aesthetic pathology”, which is a medical designation for features that deviate from some designated aesthetic norms. This article offers a two-pronged conceptual analysis of aesthetic pathology. First, I argue that three sets of claims, derived from normativist and naturalistic accounts (...) of disease, inform the framing of ugliness as a disease. These claims concern: (1) aesthetic harms, (2) aesthetic dysfunction, and (3) aesthetic deviation. Second, I introduce the notion of a hybridization loop in medicine, which merges the naturalist and normative understanding of the disease that potentially enables pathologizing practices. In the context of cosmetic surgery, the loop simultaneously promotes the framing of beauty ideals as normal biological attributes and the framing of normal appearance as an aesthetic ideal to legitimize the need for cosmetic interventions. The article thus offers an original discussion of the conceptual problems arising from a specific practice in cosmetic surgery that depicts ugliness as the disease. (shrink)