The present work illustrates the experimental results of a project aiming to assess the benefits deriving from the matrix nanomodification of composite laminates made by vacuum infusion of woven glass fabrics. The following properties have been investigated: mode I fracture toughness and crack propagation resistance for neat and clay-modified epoxy, interlaminar shear strength, mode I delamination resistance for base and clay-modified epoxy laminates.Available results indicate a significant improvement in the fracture toughness and crack propagation threshold of clay-modified epoxy. However, due to the nanofiller morphology, the behaviour of clay-modified laminates is still almost comparable to that of the base laminates.