To reveal the seepage laws and agent regulation mechanisms of fine-grained coal during high-pressure filter-press dewatering, this study takes fine-grained coal from the Pingdingshan Mining Area as the research object, and systematically conducts filter-press dewatering experiments under different pressure stages (0-5MPa) and agent conditioning (CPAM and SDBS). The results show that the fine-grained coal from Pingdingshan has fine particle size, large specific surface area, and pore size concentrated in the micron range (<5μm), leading to high specific resistance and strong adsorption characteristics of the filter cake, which are the main reasons for difficult dewatering. The effect of pressure on reducing filter cake thickness is highly consistent across different systems, all following the phasic law of "initial rapid compression, medium-pressure nonlinear transition, and high-pressure linear compaction". The addition of agents significantly enhances the compression effect of the filter cake, with the order of influence intensity being: CPAM > SDBS > no agent. Experimental data indicate that under the condition of 2.5MPa, the dewatering effect is optimal when the CPAM concentration is 40g/t, with the filter cake moisture content decreasing to 21.3%; SDBS improves the dewatering effect by reducing interfacial tension, achieving the lowest moisture content (23.9%) at a concentration of 1000g/t. In the initial stage (0–0.6MPa), CPAM and SDBS increase the compression rate by 25% and 30% respectively compared with the no-agent group; after entering the high-pressure stage (2.5–5MPa), the CPAM group exhibits the best effect, with the filter cake thickness decreasing from 19.85mm to 8.95mm and the final moisture content as low as 22.16%, while the deformation of the SDBS group and the no-agent group is relatively limited in the high-pressure stage.