Three-dimension (3D) mesoscopic structure features of polymer bonded explosives (PBXs) pressed by unidirectional and bidirectional warm die compaction (UWDC and BWDC) and isostatic warm soft compaction (IWSC) methods with the modeling granules of TATB were nondestructively studied by X-ray micro-tomography (X-μCT) technique. Results show that the initial fine crack and some residual pores are existed in the PBXs pressed by unidirectional and bidirectional compaction methods. The scale range of initial mesoscopic damage is from hundred microns to millimeter. At the same temperature (85 ℃)and pressure (90 MPa), the initial mesoscopic damage can be produced by UWDC and BWDC methods, but this damage can avoid by IWSC method.