San Dionisio del Mar

 San Dionisio del Mar  is a town and municipality in Oaxaca in south-western Mexico. It is part of the Juchitán District in the east of the Istmo de Tehuantepec region. The town is named after its patron saint.

Geography
The municipality covers an area of 237.3 km2 at an elevation of 10 meters above sea level and includes a peninsula in the Gulf of Tehuantepec on the Pacific coast. The climate is warm sub humid with summer rains. Flora include bushes, mesquite, guanacaste and native grasslands. Wild fauna include iguana, armadillo, opossum, pigeon and rook.

Demography
As of 2005, the municipality had 1,225 households with a total population of 5,165 of whom 2,639 spoke an indigenous language. The municipality is home to the Huave people, who speak a unique language unrelated to any other.

Economy
The main economic activity is fishing. The people also practice agriculture, growing maize, sesame, sorghum, squash and fruit, and keep cattle, horses and pigs.