鄂毕河（俄语：Обь）位于西伯利亚西部，是俄罗斯第四长河，也是世界上的一条著名长河。鄂毕河位于西伯利亚三大河最西侧，注入北冰洋鄂毕湾，鄂毕湾也是世界最长的河口。

鄂毕河在当地不同民族中有不同的名字，奥斯蒂亚克人（Ostyak）称为As, Yag, Kolta以及 Yema，撒摩耶人（Samoyede）称为Kolta或者Kuay，西伯利亚鞑靼人称为Omar或者Umar。

The Ob River (Russian:Обь;IPA: [opʲ]), also Obi, is a major river in western Siberia, Russia and is the world's seventh longest river. It forms at the confluence of the Biya and Katun rivers which have their origins in the Altay Mountains. It is the westernmost of the three great Siberian rivers that flow into the Arctic Ocean (the other two being the Yenisei River and the Lena River). The Gulf of Ob is the world's longest estuary.