In order to improve the tensile lap shear strength and durability of adhesively bonded joints, nano-size carbon black particles were dispersed in the adhesive using a 3-roll mill. The effect of nano-particles on the mechanical properties of the adhesive and the lap shear strength of the adhesively bonded joints composed of glass/epoxy composite were investigated at room and cryogenic temperatures. From the experimental and FE analysis results, it was found that the carbon black particles improved the mechanical property of the adhesive at room temperature, but there was no reinforcing effect at cryogenic temperature. However, since the carbon black reinforced adhesive decreased thermal residual strain in the adhesively bonded joint, the lap shear strength was improved at both room and cryogenic temperatures. Also it was found that the reinforcement with carbon black improved durability of the adhesively bonded joints under thermal loadings. (C) Koninklijke Brill NV, Leiden, 2009