São Sebastião da Vargem Alegre is a Brazilian municipality in the state of Minas Gerais. It lies within the mesoregion of Zona da Mata and the microregion of Muriaé.
The municipality was created by Law number 12.030 of December 21, 1995, when it was emancipated from Miraí. The emancipation was put to a vote, in which nearly 1,210 people participated and 81.8 percent approved the measure.
As of 2020, the estimated population of São Sebastião da Vargem Alegre was 3,024.