Barangay San Agustin I

Barangay San Agustin I is a small barangay in the municipality of Naujan, located in the province of Oriental Mindoro, in the MIMAROPA Region region of the Philippines.

According to the 2020 Philippine census, Barangay San Agustin I had a population of 1,898. This made it the 21st largest of 70 barangays in Naujan by population, placing it in the upper half of the municipality. Residents of Barangay San Agustin I accounted for approximately 1.73% of the total population of Naujan, which stood at 109,587 in the same census year.

The barangay recorded 1,605 residents in the 2015 intercensal count and 1,898 residents in the 2020 Census — a net change of +18.3%, consistent with a growing settlement. Barangay San Agustin I is officially classified as rural, a designation applied to barangays with lower population density and predominantly non-built-up land use.

Naujan is a municipality comprising 70 barangays, and serves as the governing unit directly responsible for local services in Barangay San Agustin I, including public health, sanitation, peace and order, and civil registration. Within the wider province of Oriental Mindoro, which contains 426 barangays across its component cities and municipalities, Barangay San Agustin I ranks 188th by 2020 population. Oriental Mindoro is classified as a 1st by the Bureau of Local Government Finance, a category that reflects the province's annual regular income.

Barangay San Agustin I is governed by an elected Sangguniang Barangay composed of a Punong Barangay and seven kagawads, with the Sangguniang Kabataan representing the youth. The next BSKE, set for Monday, November 2, 2026, will elect officials to four-year terms as provided under Republic Act No. 12232.