Biomimetic extracellular matrix (ECM) topographies driven by the magneticfield-directed self-assembly of ECM protein-coated magnetic beads are fabricated. This novel bottom-up method allows us to program isotropic, anisotropic, and diverse hybrid ECM patterns without changing other physicochemical properties of the scaffold material. It is demonstrated that this 3D anisotropic matrix is able to guide the dendritic protrusion of cells.