Abstract Eugene O'Neill's autobiographical tragedies, such as Dynamo, Days Without End, The Iceman Cometh and More Stately Mansions, are characteristic of the misogynistic murder motif. In these tragedies, the male protagonists actually kill or are motivated to kill their mistresses, wives and mothers. We argue that this unique phenomenon is in essence a matricide in disguise, which originated from August Strindberg's philosophy of misogyny and O'Neill's own adolescent psychological trauma. The revelation of O'Neill's misogynistic murder motif and its genealogical origin from the perspective of biographical criticism helps to explicate the dramatist's sense about the tragic fate of human beings.