尼萨河（捷克语：Lužická Nisa；德语：Lausitzer Neiße；波兰语：Nysa Łużycka），奥得河主要支流之一。

尼萨河发源于捷克苏台德山脉的西部支脉伊泽拉山脉中，向北流入奥得河，全长252公里，其中下游198公里作为奥得-尼萨线的一部分成为了今日德国和波兰的南段边界。

The Lusatian Neisse (Czech:Lužická Nisa; German:Lausitzer Neiße; Polish:Nysa Łużycka; Upper Sorbian: Łužiska Nysa; Lower Sorbian: Łužyska Nysa) is a 252-kilometre (157 mi) long river in Central Europe. It rises in the Jizera Mountains near Nová Ves nad Nisou, Czech Republic, reaching the tripoint with Poland and Germany at Zittau after 54 kilometres (34 mi), and later forming the Polish-German border for a length of 198 kilometres (123 mi). The Lusatian Neisse is a left-bank tributary of the river Oder, into which it flows between Neißemünde-Ratzdorf and Kosarzyn north of the towns of Guben and Gubin.