Glass fiber composites are preferred as 3D printed materials for aerospace applications for their improved stiffness, strength and toughness. However, the effects of the anisotropy of printed material's microstructure on their mechanical properties are still not fully understood. The microstructure of a printed material is first quantitatively investigated via X-ray computed tomography, in terms of porosity and fibers size and orientation distributions. The DIC and DVC analysis of a complex ex situ compression test is then presented. Several fracture mechanisms are observed.