This article deals with the study of the structural modifications induced in yttria-stabilized zirconia implanted with low-energy (30 keV) He ions. For this purpose, three complementary analysis techniques, namely RBS/C, XRD and TEM, were used. After implantation at 5 x 10(16) cm(-2) (similar to 4 at% to similar to 1.7 dpa), it is found that the disorder level is weak, and the damage likely consists in small interstitial-type defects and helium-vacancy clusters. These defects induce a tensile strain gradient in the direction normal to the implanted crystal surface. This weak damage indicates a strong mechanical resistance of the zirconia matrix against He implantation. (c) 2010 Elsevier B.V. All rights reserved.