Let T(d) = R(d)/Z(d) be the d-dimensional flat torus. We establish for d = 2, 3 uniform upper and lower bounds on the restrictions of the eigenfunctions of the Laplacian to smooth hyper-surfaces with non-vanishing curvature. To cite this article: J. Bourgain, Z. Rudnick, C R. Acad. Sci. Paris, Ser. I 347 (2009). (C) 2009 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.