The 1st federal electoral district of Oaxaca () is one of the 300 electoral districts into which Mexico is divided for elections to the federal Chamber of Deputies and one of 10 such districts in the state of Oaxaca.
It elects one deputy to the lower house of Congress for each three-year legislative period by means of the first-past-the-post system. Votes cast in the district also count towards the calculation of proportional representation ("plurinominal") deputies elected from the third region.
The current member for the district, elected in the 2024 general election, is Miriam de los ÃÂngeles Vázquez Ruiz. Originally elected for the Labour Party (PT), on 19 September 2024 she announced she was joining the National Regeneration Movement (Morena).
Under the 2023 districting plan adopted by the National Electoral Institute (INE), which is to be used for the 2024, 2027 and 2030 federal elections, the 1st district comprises 257 precincts () across 17 of the state's municipalities in the Papaloapan region.
The head town (), where results from individual polling stations are gathered together and tallied, is the city of San Juan Bautista Tuxtepec. The district reported a population of 435,146 in the 2020 Census and, with Indigenous and Afrodescendent inhabitants accounting for over 62% of that total, it is classified by the INE as an indigenous district.