We analyze the asymptotic behaviour of a 3D Lagrangian averaged Navier-Stokes α-model (3D LANS−α) with delays. In fact, we apply the theory of pullback attractors to ensure the existence of a pullback attractor, and at the same time, we also prove the existence of a uniform (forward) attractor in the sense of Chepyzhov and Vishik. Instead of working directly with the 3D LANS−α model, we establish a general theory for an abstract delay model and then we apply the general results to our particular situation.