Abrasive waterjet peening is a preferable alternative to traditional shot peening which can be used for surface strengthening of structural components. The fatigue crack behavior of 2024 aluminum alloy specimen treated by abrasive waterjet peening was investigated in this paper. The jet flow field was analyzed firstly by adopting CFD. The peening process was then modeled to calculate the residual stress distribution on the target surface, and the results were verified by experiments. The numerical model for the fatigue test was then established for evaluating the crack growth characteristics in the specimen with residual compression induced by the peening. The results indicated that the effective stress intensity factor range and the crack propagation rate are reduced due to the peening induced residual stress. The crack closure coefficient decreases with an increase of the shot peening intensity, while increases with an increase of the stress ratio.