Abstract – the aim of the present work is the elaboration of nanostructured polyurethane rigid foams within the inclusion of oMMT as a treated Nano clay(PUR/oMMT). The contents of oMMT are 2, 3, 5 and 10wt %. The nature expected by these rigid foams is the fire and impact proof behavior.The nanostructured materials were performed in two stages, firstly by the use of twin screw extruder (TSE)in contrarotative mode in which the blended polyols (CPP) were included between the MMT layers after treatment within the alkyl ammonium C18. And secondly the main urethanization reaction is performed using the combined processes:reaction injection molding (RIM) and controlled expansion to get pieces having parallelepiped shape. Both of later processes were performed by an appropriate montage. Various characterization methods toward reactants and Nano clays were used such as: FTIR, DSC, XRD and micro XRF. Adding the use of SEM and XRD behavior for the final items. The normalized inflammability test according to the UL 94 and tensile strength for the solid specimens was also performed. From the results it’s found that these new materials exhibit an enhancement of tenacity and notable flame retardant character obviously for the threshold content which levels off at 2 wt. % of oMMT. Key words :nanostructured, PUR rigid foam, oMMT, TSE, RIM, impact strength, fire proof.