Dispersion of nano-sized, silicate-based filler in epoxy resin is expected to yield improved materials properties in several areas. Various mechanical properties, specifically improved fracture toughness, as well as improved flame-retardant effects are of interest. The final objective of the research is investigating whether a nano-modified epoxy matrix yields improved delamination resistance in a fiber-reinforced laminate compared to a laminate with neat epoxy as matrix material. As a first step towards this goal, the fracture toughness of nano-modified epoxy resin is compared with that of the neat resin. Fracture toughness improvement up to about 50% and energy release rates increased by about 20% are observed for addition of 10 wt.% of organosilicate clay.