The name Dumangas is a combination of the Kinaray-a word "duro" which means many and the Spanish word "mangas". The place also has a bounty of mangoes. Noon time and the heat is scorching when a Spaniard came to the place. He inquire to a native in his own native language about the name of the community. The native who was asked could not understand what Spaniard had said and in fear of the foreigner struggles to utter a word. Thinking that what he is asking is the name of the tree, that the shelter gives pleasure to the traveler had responded "Dos Manggas," which means a couple of mango trees.
According to a version, the name of "Sitio Du (de) Manggas" was given by a Spanish French expedition leader of Legazpi here in Panay. He could not pronounce "de" (meaning of) instead he uttered "du". So on his report to Legazpi, he mentioned "Sitio Du Mangga," a place abundant of mangoes. Legazpi thought that was the real name of the area, so in making the early maps that name was used for that particular place. Shortly after, the name of the place was shortened to Dumangas.
Anothe theory tells that when Captain de Haya arrived in this place from Cebu, he saw a lot of people are wearing barong with "camisa de chino" with long sleeves (manggas). There were also lots of mangoes being sold since its market day. Eventually it was shortened to Dumanggas.