for the village in Nepal see Siuna, Nepal

Siuna is a municipality in the North Caribbean Autonomous Region (RACN), Nicaragua, located approximately 318 km from the capital city of Managua and 218 km from the coastal city and capital of the RACN, Puerto Cabezas. Siuna is the name of the city as well as the municipality. The municipality of Siuna contains 204 rural communities and 20 neighborhoods. The total population of the municipality is 97,308 inhabitants.