Physical violence and social conflict have been widely studied in the ancient societies of the Andes. However, studies about violence are scarce for the Formative period of northern Chile (1000 BC-AD 900). Evidence from these investigations is generally interpreted as interpersonal violence, whose protagonists are mostly men. Here, we present the case of an adult female recovered from the Tarapaca 40 cemetery (Tarapaca region, Chile) displaying lesions suggestive of trauma. We reconstruct her life and death in the context of this era's social and political conditions. Results of our bioanthropological characterization, cranial trauma analysis, carbon and nitrogen isotope analysis, and recording of the funerary offerings suggest she was a local member of the Formative community buried in the Tarapaca 40 cemetery and that she suffered intentional lethal lesions. Her death is unusual because there are no previous bioarchaeological records of lethal violence against women in the Tarapaca region. The osteobiography of this woman reflects a context characterized by an increase in inequality and social complexity, whereby physical violence could be used as a mechanism of internal regulation and exercise of power during the Formative period.