Copinula River (Rio Copinula) is a medium stream in the Sonsonate department of El Salvador, which has moderate to large quantities of fresh water year round, especially from early May through October.
A stream with a similar name, Copinulapa River (Rio Copinulapa), is also located in El Salvador, near the municipality of Nombre de Jesús in the Chalatenango department. This stream is a tributary of the Lempa River at .