Rheology of sepiolite-based epoxy suspensions as well as morphololoy and dynamic mechanical properties of the corresponding nanocomposites are discussed in this paper. The influence of the type of sepiolite used, i.e. non-modified. aminosilane and glycidylsilane Surface modified, and of the process developed to prepare the epoxy suspensions were investigated. Except for low amount of filler, a shear thinning behavior was observed in the others sepiolite-based epoxy suspensions. The interactions developed between the sepiolite and the epoxy matrix are responsible for the magnitude of the shear thinning effect and are related to the morphology of the nanocomposites. The best dispersion of sepiolite was achieved using either an emulsion process or a glycidyl functionalized sepiolite. (C) 2008 Elsevier Inc. All rights reserved.