Juan de Posada (? - ?) was a governor of Florida and Santa Elena between 1588 and 1589.
Posada was brother-in-law of governor of Florida Pedro Menéndez de Márquez, serving him in the Florida government. Eventually, he obtained the title of royal treasurer of Saint Augustine, Florida. On August 19, 1588, Menendez Marquez named him captain of the fort of Santa Elena and, in this same year, he was appointment also governor of Florida, keeping the title to 1589. He drowned in a crossing to Florida.
Juan de Posada married a sister of Pedro Menéndez Marquez. A daughter them, Maria Menendez Posada, married future governor of Florida Juan Menendez Marquez when she had only 12 years. The marriage was arranged by the uncle of both, Menendez Marquez (although, about of Juan Menendez Marquez, he only was presented as his nephew, although it is not known if he was it really). Maria Menendez inherited the title of royal treasurer of Saint Augustine of his father.