Al-5.3 wt% Cu composite reinforced with 3.0 wt% h-BN with nearly full desification was fabricated by the process of liquid-phase forging. The powder morphology and comparative structural characteristics were analyzed using X-ray diffraction, scanning and transmission electron microscopy, and the composite hardness was measured by Brinell tester. Special attention was paid to the effects of the technique on the densification and the interface bonding of as-forged composites. These revealed the composite densification can be promoted effectively with plenty of embedded liquid phase under pressure. The composites fabricated using aluminium powder with different granularity showed different grain characteristics, and in situ recrystallization occurred inside the original grains with 35 μm aluminium powder. Moreover, a good interface consisted of Al/Al2O3/BN was apparent in the composite. Compared with the basis alloy, the composite hardness was increased nearly by 15%, and the composite with 2 μm aluminium powder showed the better performance.