Objective: The purpose of this paper is to provide a review of the existing literature on racial disparities in quality of palliative and end-of-life care and to demonstrate gaps in the exploration of underlying mechanisms that produce these disparities. Background: Countless studies over several decades have revealed that our healthcare system in the United States consistently produces poorer quality end-of-life care for Black compared with White patients. Effective interventions to reduce these disparities are sparse and hindered by a limited understanding of the root causes of these disparities. Methods: We searched PubMed, CINAHL and PsychInfo for research manuscripts that tested hypotheses about causal mechanisms for disparities in end-of-life care for Black patients. These studies were categorized by domains outlined in the National Institute of Minority Health and Health Disparities (NIMHD) framework, which are biological, behavioral, physical/built environment, sociocultural and health care systems domains. Within these domains, studies were further categorized as focusing on the individual, interpersonal, community or societal level of influence. Results: The majority of the studies focused on the Healthcare System and Sociocultural domains. Within the Health Care System domain, studies were evenly distributed among the individual, interpersonal, and community level of influence, but less attention was paid to the societal level of influence. In the Sociocultural domain, most studies focused on the individual level of influence. Those focusing on the individual level of influence tended to be of poorer quality. Conclusions: The sociocultural environment, physical/built environment, behavioral and biological domains remain understudied areas of potential causal mechanisms for racial disparities in end-of-life care. In the Healthcare System domain, social influences including healthcare policy and law are understudied. In the sociocultural domain, the majority of the studies still focused on the individual level of influence, missing key areas of research in interpersonal discrimination and local and societal structural discrimination. Studies that focus on individual factors should be better screened to ensure that they are of high quality and avoid stigmatizing Black communities.