The Pasión River (Spanish: Río de la Pasión) is a river located in the northern lowlands region of Guatemala.
The river is fed by a number of upstream tributaries whose sources lie in the hills of Alta Verapaz. These flow in a general northerly direction to form the Pasión, which then tends westwards to meet up with the Salinas River. At this confluence the greater Usumacinta River is formed, which runs northward to its eventual outlet in the Gulf of Mexico.
The Pasión River's principal tributaries are the San Juan River, the Machaquila River, and the Cancuén River. The riverine drainage system of the Pasión and its tributaries covers an area of over 5,000 km², and forms a watershed for a substantial portion of the present-day Guatemalan department of Petén's western half.
The Pasión river basin is recognized as an archaeological region or zone, and contains a number of archaeological sites of the pre-Columbian Maya civilization, which to an extent shared some commonalities in Maya architectural style, political history and glyphic conventions.