Bilingual character Armando, who will be portrayed by 26-year-old Puerto Rico-born actor Ismael Cruz Cordova, will debut in September on the long-running series of people and puppets that airs on public broadcaster PBS.
"Like his character 'Mando,' Ismael represents a culturally fluid and deeply layered new generation of Hispanic-Americans," Carol-Lynn Parente, executive producer of "Sesame Street," said in a statement.
"He has a passion for creative expression and a warmth that comes right through the camera," Parente added.
"Sesame Street" previously added two bilingual Spanish-speaking actors and one bilingual puppet, Rosita. Puppet Ovejita, who only speaks Spanish, appears occasionally.
The United States is on a path to becoming a "majority minority" nation as minority babies topped 50 percent for the first time in 2011, with Hispanics the largest and fastest-growing minority group.
"Sesame Street," which is entering its 44th season, is produced by the non-profit Sesame Workshop in New York.
(Reporting by Eric Kelsey; Editing by Piya Sinha-Roy and Vicki Allen)