Epoxy nanocomposites reinforced by nanosized sepiolite are investigated. Sepiolite particles and the nanocomposites were characterized by SEM, TEM, XRD, and IR. The level of reinforcement is assessed from impact strength and flexural strength. It is shown that significant improvement in mechanical property is obtained for all reinforced nanocomposites and the addition of 1% sepiolite appears to be an optimum blend ratio.