Based on three different two-dimensional steps, the effect of turbulence model on recirculation, temperature, velocity, pressure and reattachment distance behind a step in supersonic flow were investigated numerically. Main conclusions are as follows. It's better to use one of k-ω standard, k-ω SST, RSM and SA turbulence model to capture the secondary recirculation just behind the step. For an accuracy temperature distribution, k-kl-ω turbulence model is a good candidate. For accurate velocity distribution, RSM turbulence model is a good candidate. It is well to capture the lip shock using k-ω standard or k-ω SST turbulence model. The use of k-ω standard, k-ω SST, SST4eqn or RSM is a better choice for capturing the pressure distribution, but the k-ε family isn't well. The reattach point captured by the use of k-ω SST or k-ε RNG is consistent with the experiment. The k-ω SST turbulence model is a good candidate for capturing distribution of recirculation zone, temperature, velocity, pressure and reattaches distance.