In this paper, we study the existence and multiplicity of solutions for the following fractional problem involving the Hardy potential and concave-convex nonlinearities:where Ω ⊂ R n is a smooth bounded domain in R n containing 0 in its interior, and f, g ∈ C(Ω) with f + , g + ≡ 0 which may change sign in Ω. We use the variational methods and the Nehari manifold decomposition to prove that this problem has at least two positive solutions for λ sufficiently small. The variational approach requires that 0 < α < 2, 0 < s < α < n, 1 < q < 2 < p ≤ 2 * α (s) := 2(n−s) n−α , and γ < γH (α), the latter being the best fractional Hardy constant on R n .