Senegalia greggii, formerly known as Acacia greggii, is a species of tree in the genus Senegalia native to the southwestern United States and northern Mexico, from the extreme south of Utah south through southern Nevada, southeast California, Arizona, New Mexico and western Texas to Baja California, Sinaloa and Nuevo León in Mexico. The population in Utah at 37°10' N is the northernmost naturally occurring Senegalia species anywhere in the world.

Senegalia is a genus of flowering plants in the family Fabaceae. It belongs to the Mimosoid clade. Until 2005, its species were considered members of Acacia. The genus was considered polyphyletic and required further division, with the genera Parasenegalia and Pseudosenegalia accepted soon after.