This paper will critically examine the influence of scientism in end-of-life debates. While the appropriate role of science in determining solutions to bioethical dilemmas has been a central subject in bioethics for many years, there has arguably not been much precise work done on the influence of scientism in bioethical debate. I will focus my discussion on precisely defining varieties of scientism and examine how they affect end-of-life debates. First, I will bring to the surface the metaphysical and epistemic factors in contemporary attempts to define death. Second, I will argue that many so-called scientific definitions of death obscure these philosophical factors, and are in some cases instances of scientism. I will identify the particular kinds of scientism involved in different cases and provide examples of epistemic, ontological and moral scientism. Finally, I will argue that some arguments regarding organ procurement, assisted suicide, and euthanasia are scientistic. I conclude with some general recommendations for how to recognize when a bioethical argument is scientistic or involves scientistic premises.