Haopterus is a genus of pterodactyloid pterosaur from the Barremian-Aptian-age Lower Cretaceous Yixian Formation of Liaoning, China.

It consists of the front half of a subadult, including a skull, lower jaws, pectoral girdle, sternum, wings, cervical and dorsal vertebrae, partial pelvis and metatarsals.

Haopterus was by Wang classified as a member of the Pterodactylidae, mainly because of the combination of robust teeth with the lack of a skull crest.

[2] The cladogram below follows Witton's 2012 analysis:[3] Pterodactylus antiquus Pteranodon longiceps Coloborhynchus spielbergi Hongshanopterus lacustris Haopterus gracilis Nurhachius ignaciobritoi Longchengpterus zhaoi Istiodactylus latidens Istiodactylus sinensis Liaoxipterus brachyognathus The cladogram below is a topology recovered by Kellner et al. (2019).

In the analyses, they recovered Haopterus as the sister taxon of Mimodactylus within the family Mimodactylidae, and placed within the more inclusive group Istiodactyliformes.

[4] Haopterus Mimodactylus Hongshanopterus Nurhachius Istiodactylus Liaoxipterus The authors concluded that its slender hindfeet meant that it was forced to move quadrupedally on land, suggesting a piscivore lifestyle as a specialised soarer.

[5] Although its close relative Mimodactylus was considered to be a faunivore feeding on crustaceans, suggested by Kellner et al., 2019.