The hydrodynamic performance of 6 tandem asynchronous flapping foils (TAFFs), referring to the Wave Glide propulsor, was calculated based on the RANS equations by adopting the  dynamic mesh method. The relationship between the freestream velocity, flapping angle, distance between TAFFs, active period and flapping amplitude were investigated and a  prototype was built. The results show that TAFF represents different performances at different locations. TAFF can produce higher propulsion than a single asynchronous flapping foil. The characteristics of the wake were analyzed and the reason for TAFF’s different performance was found to be the interaction between TAFF’s wake which was advantageous for propulsive. It can produce higher propulsion when the distance between TAFFs  is shorter.