What is a Guayabera shirt and when is it worn? The also known as Camisa de Yucatán is a men's summer shirt, worn outside the trousers, distinguished by two vertical rows of closely sewn pleats running the length of the front and back of the shirt. Typically made of linen, silk, or cotton, and appropriate for hot or humid weather, guayaberas are popular in Cuba, the Caribbean [especially the Dominican Republic, and Puerto Rico], Mexico, Central America, South America, Southeast Asia, the south of Spain and Portugal. What is a Guayabera shirt and when is it worn? The also known as Camisa de Yucatán is a men's summer shirt, worn outside the trousers, distinguished by two vertical rows of closely sewn pleats running the length of the front and back of the shirt. Typically made of linen, silk, or cotton, and appropriate for hot or humid weather, guayaberas are popular in Cuba, the Caribbean [especially the Dominican Republic, and Puerto Rico], Mexico, Central America, South America, Southeast Asia, the south of Spain and Portugal. What is a Guayabera shirt and when is it worn? The also known as Camisa de Yucatán is a men's summer shirt, worn outside the trousers, distinguished by two vertical rows of closely sewn pleats running the length of the front and back of the shirt. Typically made of linen, silk, or cotton, and appropriate for hot or humid weather, guayaberas are popular in Cuba, the Caribbean [especially the Dominican Republic, and Puerto Rico], Mexico, Central America, South America, Southeast Asia, the south of Spain and Portugal.