The effects of sintered porosity, volume fraction and particle size of silicon carbide particles (SiCp) on the abrasive wear resistance of powder metallurgy (P/M) aluminium alloy 6061 matrix composites have been studied. Aluminium alloy 6061 manufactured following the same route was also included for direct comparison. The results show that the beneficial effect of hard SiCp addition on wear resistance far surpassed that of the sintered porosity in the P/M composites. Tremendous improvements in the wear resistance of aluminium alloy can be expected by adding the SiCp reinforcements. The wear rates of composites decreased as the amount of SiCp increased. For the composites containing the same amount of SiCp reinforcements, the wear rates decreased with increasing SiCp size. Aluminium alloy composites reinforced with larger SiCp size are more effective against abrasive wear than those reinforced with smaller SiCp size. The wear rates of the P/M aluminium alloy and 10 vol.% SiCp composite were significantly affected by the aging conditions. However, for the 20 vol.% SiCp composite, and for the composites with large SiCp size, the aging effect on the wear rate of the composites was found to be small.