The Procellariidae family are a group of seabirds in the bird order Procellariiformes, which also includes the Albatross family Diomedeidae, the storm-petrels Hydrobatidae, and the diving petrels Pelacanoididae.

The family Procellariidae is the main radiation of medium-sized 'true petrels', characterised by united nostrils with medium septum, and a long outer functional primary. It is dominant in the Southern Oceans, but not so in the Northern Hemisphere.

It includes:

• The fulmar group
  • The huge giant petrels, genus Macronectes, which are convergent with the albatrosses.
  • The fulmars, genus Fulmarus
  • Antarctic Petrel, Thalassoica antarctica
  • Cape Petrel, Daption capense
  • Snowy Petrel, Pagodroma nivea.
• The petrel group
  • The gadfly petrels. These are large and agile short-billed petrels in the genus Pterodroma.
  • The four Bulweria species
  • Kerguelen Petrel Lugensa brevirostris
  • Tahiti Petrel Pseudobulweria rostrata.
• The prionss, genus Pachyptila. A specialised group of six very numerous species, all southern. They have a small, fulmar-like form and filter-feed on zooplankton.
  • The Blue Petrel Halobaena caerula is allied to the prions.
• The Shearwaters in the genera Calonectris, Puffinus and Procellaria. The four species in the last genus are named petrels, but are genetically closer to the shearwaters.