The Prahova is a river of Southern Romania, which rises from the Bucegi Mountains, in the Southern Carpathians. It is a left tributary of the Ialomița. It flows into the Ialomița in Dridu Snagov. The upper reach of the river, upstream of the confluence with the river Azuga is sometimes called the Prahovița.
It has a length of , of which are in Brașov County, are in Prahova County and the last are in Ialomița County.
The basin of the Prahova covers ,