Unusual self-organization of sepiolite fibbers have been found during the synthesis of sustainable nanocomposites. These auto-structured networks are synthesized starting with an epoxidized linseed oil (ELO), a bio-based hardener of dicarboxylic class and sepiolite fibbers. For the first time, the auto-organization of sepiolite fibbers into empty or solid spheres insight a bio-based thermoset matrix have been highlighted and synthesized. The influence of the thermoset formulation and the sepiolite concentration on self-organization are emphasized. The thermomechanical properties of nanocomposites have been investigated highlighting an increasing of elastic modulus from 30 to 40 % in the vitreous states and from 25 to 45 % in the rubbery state. This peculiar organization and behaviour of sepiolite, similar to that of surfactants, is of great interest as fundamental, applicative and industrial level.