Ostromia (Thick feet of John Ostrom) is a genus of anchiornithid theropod dinosaur from the Late Jurassic Painten Formation of Germany.

The holotype was discovered near Riedenburg, Germany in 1855 and it was originally misidentified as a species of a pterodactyloid pterosaur and named Pterodactylus crassipes in 1857.

While such structures can be a result of collapsed or broken bones (as is the case in several Archaeopteryx specimens), the straight, smooth edges of the furrows in Ostromia and Anchiornis indicate that they are legitimate biological features.

[2] Agnolin et al. (2019) argued that the putative anchiornithid affinities of Ostromia are also seen in Unenlagiinae, and that it is best to consider this genus as an indeterminate paravian.

[3] In contrast, Foth et al. (2025) still recovered the same conclusion that Ostromia is an anchiornithid based on their phylogenetic analysis.