Simón Vega creates drawings, objects, sculptural installations and happenings inspired in local markets, self-made-architecture and vendor carts found in the streets and beaches of Central America. His sculptures are Third World replicas of the  sophisticated capsules and satellites developed by NASA and the Soviet Space Program during the 'Space Race', however, they are assembled with found materials and they include transmutable elements, colored lights and live plants. This series, titled Tropical Space Proyectos comments on the effects of the Cold War in contemporary El Salvador and Central America. In other works the artist combines 1980s science fiction and futuristic characters with repurposed metal objects and colorful materials like discarded sandals and plastic found in the beach to create Third World, tropicalized versions of these robotic humanoids, fusing First World high technology with do-it-yourself methods and repurposed materials to create masks and other objects that also recall Mesoamerican and Afro-Caribbean cultures.
He has exhibited his work extensively in Europe, the United States and Latin America, including the 55th Venice Biennial in Italy (2013), the IX Havana Biennial, in Cuba (2006), at the Coachella Music Festival in Indio, California (2018), at the Bronx Museum in New York (2019), at the Centre Pompidou, Paris for the exhibition Cosmópolis 2 (2019), at the Oku Noto Triennial in Suzu, Japan (2021) and at the Reina Sofía Museum in Madrid (2023). He has participated in solo exhibitions notably at the Museum of Contemporary Art and Design, Costa Rica; Locust Projects, Miami; and the Parish Art Museum, Hamptons.