In recent years, Metamaterials, artificial electromagnetic materials that are constructed by sub-wavelength units, have demonstrated unusual abilities to manipulate electromagnetic waves and promised many potential applications. One of the most intriguing applications of metamaterials is to function as high performance absorbing medium. In this work, a new type of plasmonic flexible metasurface-based super-absorber for Terahertz waves is designed, fabricated and characterized. Dependences of absorption on the optical properties of component materials and geometric parameters are optimized by full-wave numerical simulations, and then confirmed by experiments. Experimental results show that an absorption peak value of 99% is obtained at the frequency of 3 THz, which are in good agreement with numerical simulations.