The family Dilophosauridae was proposed by Alan Charig and Andrew Milner in 1990 to contain only the type genus, Dilophosaurus.
Other genera, such as Zupaysaurus and Dracovenator, have since been assigned to this family, though the group has never been given a phylogenetic definition and is not currently a clade.
Some studies have suggested that there was a natural group of medium-sized crested theropods which included Dilophosaurus as well as Dracovenator, Cryolophosaurus, and Sinosaurus, though it has not been formally named Dilophosauridae.
While traditionally assigned to the superfamily Coelophysoidea, these analyses suggest that dilophosaurids may have been more closely related to the group Tetanurae, comprising the more advanced megalosaurs, carnosaurs and coelurosaurs.

The following cladogram outlines the relationships of Dilophosaurus and its close relatives as recovered by the 2007 analysis of Smith, Makovicky, Pol, Hammer, and Currie.

In 2015, Hendrickx et al.
proposed a family tree that reflects a more restricted view of the family Dilophosauridae.
Although Dilophosauridae previously included Dilophosaurus, Dracovenator, Sinosaurus, and Crylophosaurus, recent research has supported a more narrowly defined family Dilophosauridae containing only Dilophosaurus and Dracovenator and excluding Sinosaurus and Crylophosaurus.
This change was supported by similarities between Dracovenator, Dilophosaurus wetherilli and Zupaysaurus rougieri, suggesting these taxa might form their own clade sister to Dilophosauridae, although there is no definitive evidence.
Sinosaurus and Crylophosaurus are also now classified as basal tetanurans.
While all of the dinosaur genera once within Dilophosauridae are characterized by a distinctive cranial crest, it is thought that this distinctive trait was convergently evolved in dilophosaurids and basal tetanurans, and thus not all are necessarily derived from the same common ancestor.

The following family tree illustrates a synthesis of the relationships of the early theropod groups compiled by Hendrickx et al.
in 2015, and follows more recent research showing a more restricted Dilophosauridae.
The family Dilophosauridae was proposed by Alan Charig and Andrew Milner in 1990 to contain only the type genus, Dilophosaurus. Other genera, such as Zupaysaurus and Dracovenator, have since been assigned to this family, though the group has never been given a phylogenetic definition and is not currently a clade. Some studies have suggested that there was a natural group of medium-sized crested theropods which included Dilophosaurus as well as Dracovenator, Cryolophosaurus, and Sinosaurus, though it has not been formally named Dilophosauridae. While traditionally assigned to the superfamily Coelophysoidea, these analyses suggest that dilophosaurids may have been more closely related to the group Tetanurae, comprising the more advanced megalosaurs, carnosaurs and coelurosaurs.
The following cladogram outlines the relationships of Dilophosaurus and its close relatives as recovered by the 2007 analysis of Smith, Makovicky, Pol, Hammer, and Currie.
In 2015, Hendrickx et al. proposed a family tree that reflects a more restricted view of the family Dilophosauridae. Although Dilophosauridae previously included Dilophosaurus, Dracovenator, Sinosaurus, and Crylophosaurus, recent research has supported a more narrowly defined family Dilophosauridae containing only Dilophosaurus and Dracovenator and excluding Sinosaurus and Crylophosaurus. This change was supported by similarities between Dracovenator, Dilophosaurus wetherilli and Zupaysaurus rougieri, suggesting these taxa might form their own clade sister to Dilophosauridae, although there is no definitive evidence. Sinosaurus and Crylophosaurus are also now classified as basal tetanurans. While all of the dinosaur genera once within Dilophosauridae are characterized by a distinctive cranial crest, it is thought that this distinctive trait was convergently evolved in dilophosaurids and basal tetanurans, and thus not all are necessarily derived from the same common ancestor.
The following family tree illustrates a synthesis of the relationships of the early theropod groups compiled by Hendrickx et al. in 2015, and follows more recent research showing a more restricted Dilophosauridae.
Dilophosauridae