Atrai River (also spelt as Atreyee) (Bengali: আত্রাই/আত্রেয়ী নদী, romanized: ātrāi/ātrēẏī nadī) flows in West Bengal in India and northern parts of Bangladesh.

The Atrai originates in Siliguri ward no 40, near Baikanthapur forest of West Bengal and after flowing through Dinajpur District of Bangladesh, it enters India again.

[4] It passes through Kumarganj and Balurghat community development blocks in Dakshin Dinajpur district.

[4] The river serves as a perennial source of fishing, even though it is often the cause of flooding in many areas during monsoons.

[6] The total length of this river is approximately 240 miles (390 km) and its maximum depth is 99 feet (30 m).