洛尼亚河是克罗地亚的河流，位于该国中部，属于萨瓦河的左支流，河道全长133公里，流域面积5,944平方公里，河畔城镇有新马罗夫，支流有切斯马河、伊洛瓦河和帕克拉河。

Lonja is a river in central Croatia, a left tributary of the Sava. It is 133 kilometres (83 mi) long and its basin covers an area of 5,944 square kilometres (2,295 sq mi).

The Lonja rises in the Kalnik mountain in northern Croatia, southeast of Novi Marof, at 46°07′57″N 16°22′17″E / 46.132404°N 16.371417°E / 46.132404; 16.371417. It flows westward until turning south near Breznički Hum, passing east of Sveti Ivan Zelina, and turning southeast near Sveta Helena. East of Lupoglav, it turns south again, passing through Ivanić-Grad and nearing the river Sava.