Three-dimensional Flow Analysis in Complex Fracture Networks through Green's Function. Traditional simulation methods struggle with unconventional reservoirs, which have extremely low permeability and complicated natural fracture systems. Traditional numerical approaches like dual-porosity and dual-permeability models are unable to adequately account for the impact of fracture connectivity and topology, particularly in three-dimensional domains. This paper proposes a semi-analytical solution for simulating transient single-phase flow in fractured porous media using Green's functions. The approach allows for precise and effective pressure and production predictions by explicitly incorporating the geometry and connectivity of intricate fracture networks. The suggested model includes steady-state and transient fracture flow equations together with Green's functions for point, line, and plane sources obtained for an anisotropic cuboidal reservoir.