Roil Bonding process is applied to clad the core plate (U308+Al), with high strength aluminum alloys during fabrication of plate type nuclear fuel elements for research reactors, or to produce many new constructions which have special uses in industrial applications. In the present work the effect of the surface roughness of 6061 aluminum alloy plates on roll bonding interface was studied using both microscopic examination and mechanical testing. It was found that the bond strength reached a maximum value at surface roughness of about 5 21_1.m. The bond strength decreases rapidly with both decreasing or increasing the surface roughness than 5.2 um. The increase of the surface roughness resulted in the blistering area increase.