21 Members (excluding the associate or suspended members but including the countries represented on their behalf) [The rulers are not necessarily the representatives in the organisation. ] :
| | ARGENTINE | (Buenos Aires a + Olivos r) | | President Edelmiro Julian Farrell | | |
| | BOLIVIA | (Sucre cj + La Paz eir) | | President Gualberto Villarroel | | |
| | BRAZIL | (Rio de Janeiro) | | President Getulio Vargas | | |
| | CHILE | (Santiago of Chile a + Valparaiso l + Vina del Mar s) | | President Juan Antonio Rios | | |
| | COLOMBIA | (Bogota) | | President Alfonso Lopez Pumarejo | | |
| | COSTA RICA | (San Jose) | | President Teodoro Picado Michalski | | |
| | CUBA | (Havana) | | President Ramon Grau San Martin | | |
| | DOMINICAN | (Ciudad Trujillo) | | President Generalissimo Rafael Leonidas Trujillo | | |
| | ECUADOR | (San Francisco of Quito) | | President Jose Maria Velasco Ibarra | | |
| | GUATEMALA | (Guatemala City) | | President Juan Jose Arevalo | | |
| | HONDURAS | (Tegucigalpa a + Comayaguela c) | | President Tiburcio Carias Andino | | |
| | HAITI | (Port Au Prince) | | President Elie Lescot | | |
| | MEXICO | (Mexico City) | | President Manuel Avila Camacho | | |
| | NICARAGUA | (Managua) | | President Anastasio Somoza Garcia | | |
| | PANAMA | (Panama City) | | President Ricardo Adolfo de la Guardia | | |
| | PERU | (Lima) | | President Manuel Prado Ugarteche | | |
| | PARAGUAY | (Assumption) | | President Higinio Morinigo | | |
| | EL SALVADOR | (San Salvador) | | President Salvador Castaneda Castro | | |
| | AMERICA | (Washington-District of Columbia) | | President Harry Truman | | |
| | URUGUAY | (Montevideo) | | President Juan Jose de Amezaga | | |
| | VENEZUELA | (Caracas) | | President Isaias Medina Angarita | | |