The objective of this review paper is to summarize the current status, identify the knowledge gaps, and provide future directions of research on density in ceramic binder jetting additive manufacturing. This paper begins with the process overview, material considerations, and process parameters. Low density or high porosity is identified as the most challenging issue in this literature survey, therefore different aspects of density are reviewed, including various terminologies, measurement methods, and achieved values. The techniques to increase the part density are reviewed in detail in two categories: material preparation techniques (powder granulation, mixing powders of different sizes, using slurry feedstock, mixing different materials, and applying sintering additives) and post-processing techniques (sintering, chemical reaction, infiltration, and isostatic pressing). Finally, the knowledge gaps in the literature are analyzed and the corresponding future research directions are suggested, including investigations of powder spreading and powder granulation.