Equilibrium swelling was tried as a means to measure the adhesion between natural rubber (NR) and aluminium powder in their composites. NR-aluminium powder composites which contained four vulcanising systems, viz., conventional (CV), efficient (EV), dicumyl peroxide (DCP) and a mixture consisting of sulphur and dicumyl peroxide (mixed) and hexa-resorcinol-silica as dry bonding system were evaluated for this. A series of aliphatic solvents like pentane, hexane and heptane were used to study the equilibrium swelling of the composites. The results showed that addition of bonding agent reduced the swelling and are more pronounced in conventional system, due to the increased adhesion. The scanning electron microphotographs revealed more uniformity of the metal powder in the matrix in presence of hexa-resorcinol silica bonding system.