In agriculture, a milpa is a field used to grow food crops and a farming system common in Mesoamerica, especially in the Yucatán Peninsula of Mexico. The word "milpa" comes from the Nahuatl words milli and pan. Based on farming traditions of the Maya and other Mesoamerican peoples, the milpa system is used to grow maize, beans, and squash.

The milpa system follows a land-conservation cycle of two years of farming and eight years of leaving the land unused. In some areas, such as the Mexican states of Jalisco and Michoacán, central Mexico, and Guanacaste Province in Costa Rica, the term "milpa" refers to a single corn plant. In El Salvador and Guatemala, "milpa" specifically means a harvested maize crop and the field where it is grown.

The concept of milpa is more than just a farming method; it is a cultural practice that connects people to their land and each other. Farmers have strong relationships with their crops and the land, and creating a milpa is considered a sacred act. This practice unites families and communities and holds deep religious and social meaning in Mesoamerican cultures, sometimes more important than its role in providing food or income.

The city of Milpitas, California, is named after the Nahuatl word milpa with the Spanish suffix -itas, which is used to form a feminine plural diminutive.