Abstract: Bentonite and graphite, as fine as powder, are pressed into large, high-density blocks that require super-tonnage loading equipment. For solving this problem, the "Two-Step Compaction" method is proposed, that is, the fine powder particles are first pressed into high dense blocks and then broken into clusters. The pellets are then remixed with the powder particles and pressed into larger high-density blocks at lower loads. The results show that the "Two-Step Compaction" method can achieve higher density blocks prepared by the same tonnage press, and increase the block density by more than 4%, compared with direct compaction with pure powder bentonite. When the target dry density 1.93 g/cm³, the compaction stress can be reduced by 4 MPa. During the compaction process, the pellets undergo changes of "rearrangement, fragmentation, and densification". When containing 30% pellet content, the re-compacted block demonstrates optimal compaction efficiency, better forming ability and uniformity. The microscopic test shows that the "Two-Step Compaction" method can reduce the pore diameter in the re-compacted block and improve the compactness of the block.