The paper presents a research methodology for measuring the density of carbon dioxide in the solid state. Because of the sublimation of this material under normal conditions, the method based on the measurement of the geometric parameters of the sample and its weight is not accurate. For different materials, which can be characterized by a fact that their geometrical parameters or weight are not constant over time (due to different physical phenomena), the density measurement using the hydrostatic method could be a better solution. In the paper, a methodology of density measurement on the basis of a hydrostatic method is presented. A case study is densified carbon dioxide (called also like dry ice), which is in a solid-state. For this purpose, during density examination, it is necessary to apply liquids such as ethanol and isopropyl alcohol, which could be cooled to -74,5 degrees Celsius, and their liquid properties will have remained. The density of these two liquids in the considering range of temperature was determined, and after that, the preliminary dry ice density research was performed. Their results allowed to formulate the guidelines for further experimental research on the carbon dioxide densification process.