An Atreya (आत्रेय) is a descendant of Atri, one of the great Hindu sages (rishis) whose accomplishments are detailed in the Puranas.
The descendents of Atri Rishi use Atreya as their surname just like many other Gotras, or clan names used by the Brahmin community of Hindus in India and Nepal. In Northern India, most Atreya Bhramins also prefer to use the Tyagi surname. Many of the Kshatriyas of South India also belong to this Gotra.
Original Atreya gotri bramhin have migrated to East Indian state of Orissa which was in the ancient time known as Kalinga, Utkala/Utkal, South Kosal, Kongada, Odra Desha etc. All Oriya-Utkala Brahmins with surname Rath belong to the Atreya gotra in the line of rathātreya (रथात्रेय). People with the surname Paudel also belongs to this Gotra. a son of Atri and compiler of the Ṛk Veda, 5th Maṇḍala. Nepali brahmin castes like Dulal,Pokhrel,Sharma etc are known as Atreya Gotra.