Equal channel angular pressing was successfully applied on a lamellae eutectic alloy of Al-33%Cu at 400degreesC, up to an equivalent strain of similar to8. A homogeneous fine equiaxed duplex microstructure with an average grain size of 1.1 +/- 0.3 mum was obtained. Deformation accommodation is realized in various form of periodical shear banding: periodical bending, periodical shear banding, shear switching, and periodical shear cutting in the eutectic. The shear essence of the strain mode involved in ECAP determines the very different behavior, from that in drawing, of lamellae structural evolution.