Leticia Del Rosario was member of the American Physical Society and represented Puerto Rico in the Latin American Council for Cosmic Radiation ("Consejo Latinoamericano para Radiación Cósmica" (CLARC)). At UPR she was member of the Academic Senate and founder and president of the University Faculty Organization ("Organización de Profesores Universitarios"). In 1977, she was elected member of the Puerto Rico Academy of Arts and Sciences.