The Bumbungan River () is a river in the province of Laguna in the Philippines. It is commonly referred to as the Pagsanjan River because of the popularity of Pagsanjan town and Pagsanjan Falls, the province's most popular destination. The official website of Pagsanjan town and the people of Cavinti refers to the river as Bumbungan River. The municipality of Pagsanjan was named so because it is where the Balanac River, originating from Mount Banahaw, joins the Bumbungan. Its old name, Pinagsangahan, which literally means branching, was changed to Pagsanjan during the Spanish Colonial Era.