Fiber metal laminates (FMLs) are the hybrid laminates consisting of alternating thin layers of metal sheets and fiber-reinforced composite material. Interface between metal and polymer layer plays a significant role. FMLs have both low density and high relative strength, and other good properties as high damage tolerance: fatigue and impact characteristics, corrosion, and fire resistance. In present work, the microstructure of the aluminum-epoxy/glass and aluminum-epoxy/carbon composites is characterized. The interface between metal and polymer composites with surface treatment and without surface treatment at different pressures was examined. It was observed that pretreatment of the aluminum has a significant effect on the zone between metal and polymer composite. In the interface, there is a direct contact between anodizing layer and resin without fibers, the same for epoxy/glass and epoxy/carbon laminates. The low pressure in autoclave process has a detrimental effect on the structure. It is responsible for the formation of the porosity and delamination in polymer layer and interface between aluminum and polymer composites. Untreated surface of aluminum sheet is characterized by too low adhesion to epoxy composite, especially with carbon reinforcement.