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This paper presents an investigation of RANS and DES models for the Ahmed body with 25 • and 35 • slant angles. The Reynolds number, based on the height of the model and the upstream velocity, is 7.68×10 5 . Two RANS ( Reynolds Averaged Navier-Stokes) models are used: the k − ω SST of Menter and the EARSM (Explicit Algebraic Stress Model), based on the k − ω model. Two hybrid RANS-LES (Large Eddy Simulation) models are used: a DES (Detached Eddy Simulation) and an IDDES (Improved Delay Detached Eddy Simulation). These hybrid models are also based on the k − ω model. The flow for the slant angle 35 • is well predicted by all turbulence models with a slight advantage for the IDDES model. For the flow with the slant angle 25 • , only the IDDES hybrid RANS-LES model predicts the recirculation bubble on the slant. It is concluded that the IDDES model is the only turbulence model that gives good agreements with the experimental data.