San Marcelo is a corregimiento located in the Cañazas District of the Veraguas Province in Panama. It serves as a local administrative division within the country's interior.
Demographic data indicates that the population of San Marcelo has fluctuated over recent decades. As of 2010, the population was recorded at 1,476, following a decline from 3,277 in 1990 and 2,998 in 2000.