Spanish police detained the Colombian national after discovering the snack, which contained more than 100g (3.5 ounces) of cocaine.
A photo of the sandwich-stash was tweeted by @policia.
It shows a piece of bread containing slices of ham and melted cheese, as well as nine cylindrical packages wrapped in plastic.
The tweet revealed the man was arrested at Benidorm bus station and was suspected of trafficking.
Officers reportedly searched the 29-year-old’s home and discovered “more than a kilo of cocaine powder and pieces, as well as marijuana and tools to handle drugs”.
Spanish police confirmed another suspected trafficker, reportedly a 20-year-old Colombian, had been arrested.
Reports suggest the two are housemates in the coastal Mediterranean town.
Spain’s ties to Latin America have made it a common entry point for cocaine into Europe