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Recently, I had the privilege of discussing with industry experts the suitability of slurry-bed hydroprocessing feedstocks, and conducting an in-depth analysis of the slurry-bed process. It was agreed that the \"specific gravity\" of the feedstock is a key parameter in slurry-bed hydroprocessing; there is a critical relationship between safe operation of the plant and its economic efficiency and this specific gravity. At present, there are many uncertainties in the operation and control of slurry-bed hydroprocessing reactions, with numerous technical questions that need to be resolved. The commonly recognized properties of the raw materials for this process are summarized as follows: First, raw materials with properties that lie between those of catalysts and coking agents represent the best, most rational, and most economical choice. Raw materials that can produce coked pellets must be handled with care when fed into the slurry bed for processing ； II. Viscosity indicators are important parameters for evaluating the raw materials used in slurry beds; they affect the dispersity during the slurry formation process, the unit condensation rate during the reaction, the asphaltenic cracking index, and the degree of lightening. Additionally, they influence the mixing degree within the reactor, the rate at which the oil phase rises, and the second liquid phase at the bottom of the reactor ； III. The influence of asphaltenic morphology: the degree of hydrogenolysis in continental shelf structures is much lower than that in island chain structures, and the asphaltenes produced have larger molecular structures, making them more prone to collision, aggregation, condensation, and coking. In DOA materials subjected to leaching processes, the tendency toward coking becomes even more pronounced, sometimes doubling as a result of the disruption of the colloidal structure ； IV. Residual carbon is a physicochemical indicator used to assess the coking trend in coking reactions; it serves only as a reference for the conversion efficiency in slurry-bed hydrogenation reactions. Due attention should be paid to the relationship between C7/C5 asphaltenes, density, and cracking indices ； V. The molecular structures of the heteroatoms S, O, N in the raw materials and metals have a direct impact on the degree of lightening. The energy of the N-O bond and the reaction mechanism of Mo-based catalysts are the fundamental reasons for the limited ability to remove nitrogen. It is important to distinguish between inorganic ammonia, basic nitrogen, and total nitrogen in the products, in order to avoid misleading downstream processing procedures. We ask everyone to examine this carefully, share their opinions, and propose more reasonable parameters that will help to make the device lighter, improve reaction efficiency, enhance slurry homogeneity, stabilize the bed layer, extend the project duration, ensure equipment safety, and maximize benefits.