[en] Highlights: • Conformal coatings of TiO_2 on complex three-dimensional macroporous foams can be achieved by atomic layer deposition. • Atomic layer deposited coatings protect macroporous foams from intergranular corrosion in 1 mM hydrochloric acid. • Amorphous and anatase thin films have a similar protection effect up to 28 days. • Topographical surface parameters change significantly upon hydrochloric acid exposure - Abstract: Intergranular corrosion causes a significant loss of compressive strength in highly porous TiO_2 foams. In this study, the resistance of conformal atomic layer deposited (ALD) coatings against intergranular corrosion has been investigated. ALD coated TiO_2 foams maintained 107% ± 20% and 94% ± 10% of their initial compressive strength for films deposited at 150 °C and 250 °C, respectively. After an immersion period of 28 days in 1 mM HCl, amorphous films showed greater potential in corrosion protection of polycrystalline TiO_2 foams. However, anatase coatings with sufficient protection may be more beneficial for cell-material interactions.