We present a novel fully resolved coupled computational fluid dynamics (CFD) and discrete element method (DEM) to model fluid-particle interactions involving arbitrarily shaped particles. The signed distance field (SDF) plays a key role to enable consistent integration of DEM and CFD for the coupling. A SDF-based formulation is employed to offer robust and efficient treatments of granular particles with arbitrary shapes in DEM. The volume of fluid (VOF) method employed in the CFD to model multiphase fluids is adapted for the SDF to fully resolve fluid-particle interactions in the presence of non-spherical particles. The SDF serves as a generic interface to empower the new SDF-CFD-DEM framework for effective modeling of arbitrarily shaped particles interacting with multiphase fluids with desired resolutions. We use benchmark problems to validate the proposed SDF-CFD-DEM and further showcase its predictive capability with multiple demonstrative examples.