In 1821, Mexico obtained independence from Spain and most nations of Central America, including El Salvador, were a part of the First Mexican Empire under Emperor Agustín de Iturbide.

In reciprocity, Salvadoran President Carlos Meléndez sent five thousand rifles and a small group of men as requested by the Mexican Government so that they would join the constitutionalist forces and fight against Victoriano Huerta.

[1] Both nations have cooperated together in combating drug trafficking and gang violence, including MS-13 (also known as the Mara Salvatrucha) of which was the main cause of havoc in El Salvador and their operations created insecurity in the country.

In 2018, several hundreds to a few thousands Salvadorans formed part of the Central American migrant caravans and traversed all of Mexico to the northern city of Tijuana to request asylum in the United States.

[21] El Salvador's main exports to Mexico include: clothing, electrical wires and cables, household items, sugar cane, oils of petroleum and imitation jewelry.

Mexico's main exports to El Salvador include: electrical equipment and machinery, food based products, fruits, dairy, medicine, chemicals, and motor vehicles.