El Rosario National Park, National park in Sayaxché, Guatemala

El Rosario National Park is a national park in the Petén department of Guatemala, on the eastern edge of Sayaxché. It covers 11.05 km², including Laguna El Rosario, a small lake of about 4 hectares in the dry season that grows considerably in the rainy season. It was formerly a state-owned finca managed by the National Forestry Institute (INAB).

The area was established as a national park in 1980, and before that it functioned as a state-managed forest estate. Prior to official protection, the land was administered by the national forestry institute as a government finca.

The park takes its name from Laguna El Rosario, a small lake at its center. For people from Sayaxché, it serves as a nearby spot for family outings, where walking along shaded paths and sitting by the water are common ways to spend a day.

The park is easy to reach from Sayaxché on foot or by vehicle, making it a good option for a short outing. Visiting during the dry season makes walking the trails more comfortable, as paths can become slippery when it rains heavily.

El Rosario lake covers about 4 hectares in the dry season but expands considerably during the rainy season, so the park's water surface varies greatly through the year. The lake gives the park its name.