We demonstrate that the arbitrarily weak quenched disorder on the surface of a system of continuous symmetry destroys long range order in the bulk, and, instead, quasi-long range order emerges. Correlation functions are calculated exactly for the two-and three-dimensional XY model with surface randomness via the functional renormalization group. Even at strong quenched disorder the three-dimensional XY model possesses topological order. We also determine roughness of a domain wall in the presence of surface disorder. 75.10.Nr, 74.60.Ge, 05.50.+q, 64.60.Ak The arbitrarily weak quenched disorder in the bulk of a system of continuous symmetry destroys long range order inherent to the pure system [1] provided that disorder breaks not only the translational symmetry but also the symmetry with respect to transformations of the order parameter, as e.g. random anisotropy in amorphous magnets does. This fundamental fact governs all the physics of condensed matter and results in a wealth of observed static and dynamics behaviors of real solids.In many cases noticeable disorder presents only at the surface. Not surprisingly, surface randomness modifies the critical behavior near the surface [2], yet the common expectation is for the bulk properties to remain intact. In this Letter we show that arbitrarily weak surface disorder destroys long range order in the bulk of a system of continuous symmetry at the arbitrarily low temperature.The predicted effect occurs in a rich variety of systems. Examples include crystal ordering in solids grown on a disordered substrate, liquid crystals interacting with an inhomogeneous surface, superconducting vortices pinned by surface impurities, etc. There are also many two-dimensional systems with edge randomness, e.g. superconducting films with columnar defects in a part of the film or films with a rough edge [3].The reason as to why surface impurities, however weak, break long range bulk order is that the bulk contributes little to the energy of long-wave Goldstone modes: the surface random energy of long-wave excitations turns out to be greater than the corresponding bulk energy. As a result, the inhomogeneous state becomes favorable energetically. Note that ordering survives in the regions of the size less than the distance of these regions from the surface. In other words, if the distance between the two points is greater than their separation from the surface, the order parameter is different in those points. While long range order breaks down, topological order survives and quasi-long range order emerges. This means that the correlation length is infinite and that the correlation functions obey a slow logarithmic dependence of the distance.An easy way to understand the main result of the Letter is based on Imry-Ma arguments [1,4]. Let us consider a region of size L near the surface and compare the energies of ordered and disordered states of the region. If long range order is broken on the scales of the order of L the loss in the bulk (elastic) energy is E bulk ∼ L D /L 2 , where ...