Frequency-dependent seismic attenuation can be applied to indicate transport properties of fractured media and fluid mobility within it. In particular, wave-induced fluid flow (WIFF) appears during seismic wave propagation between fractures and background as well as within interconnected fractures, and causes intensive attenuation. We present effective algorithm for numerical upscaling to estimate attenuation in anisotropic fractured porous fluid-saturated media. Algorithm is based on numerical solution of quasi-static Biot equations using finite-difference approximation. Presented algorithm is used to estimate seismic attenuation in fractured media with high fracture connectivity. Results of numerical experiments demonstrate the influence of physical properties and microscale anisotropy of fracture-filling material on seismic attenuation.