With interconnecting voids, porous asphalt provides drainage of rainwater in vertical and lateral direction during rainfall. In addtition, it also offers remarkable advantages compare to traditional asphalt: reduce vehicle splash and spray behind, reduce night time surface glare in wet season and increase tire-pavement friction...On the other hand, the following aspects are recognized as disavantages: reduced performance, winter maintenance issues and high construction cost. For flexible pavement, dynamic modulus master curve is an important parameter in the mechanistic-empirical pavement design guide. In this study, the results of experiment of dynamic modulus test of porous asphalt are discussed for understanding well about the viscoelastic characteristics of porous asphalt.