A numerical investigation has been carried out for the turbulent fluid now and heat transfer in periodic fully developed corrugated ducts. Three turbulence models are used in the calculation: the standard k − ε model, the Re-Normalized Group (RNG) k − ε model and a Reynolds Stress Model (RSM). The turbulent heal flux is modeled by the simple eddy diffusivity model (SED). The numerical results were compared with corresponding experiments, and it was found that none of the models could give satisfactory predictions, although the standard k − ε model gave relatively more reasonable results. Based on the numerical results obtained by the standard k − ε model, the thermal and flow field characteristics in the periodic fully developed corrugated ducts are discussed in detail, including the influences of the Reynolds number and the inter-wall spacing.