Stathis Giallelis (Greek: Στάθης Γιαλελής; born January 21, 1941) is a retired Greek actor. He won brief international renown in the early 1960s as the star of Elia Kazan's Academy Award-nominated epic America America, a role which brought him the Golden Globe Award for New Star of the Year – Actor, as well as a nomination for Golden Globe Award for Best Actor – Motion Picture Drama.

Giallelis' entire prominence revolves around his central role in America America. He appears in nearly every scene of the 174-minute film and gives what some critics described at the time as a "towering performance". He has not, however, faced a camera since 1980 and his biographical details remain sketchy. The date of his birth is generally accepted as correct, although two sources indicate 1939 as the year. All listings agree that he was born in Greece, but none specify the location. The medium-height, slightly built Giallelis was twenty-one years old in mid-1962, upon Elia Kazan's arrival in Greece looking for someone who could capture his uncle's life in 1890s Anatolia and the struggle to achieve his determined dream of immigrating to the United States. Kazan wanted an unknown actor in whom the audience would see the character rather than the familiar face. In his autobiography, Elia Kazan: A Life, the director describes the details of his search for "a ferret, not a lion", someone who, like his uncle, did not always behave honorably, but had "my boy's single redeeming quality, devotion to his father and family".

Kazan first tried to find his leading actor in England and, subsequently, in France, where a likely candidate was found, tested and rejected as "too handsome" and "lacking desperation". Even the Actors Studio proved deficient in providing the ideal aspirant. Finally, as he described it, "I did the obvious, went to Athens, and in the office a film director found an apprentice sweeping the floor so he could be near production work". This was the office of Greek producer/director Daniel Bourla. Unfortunately, Giallelis was severely limited in both acting experience and knowledge of English. The only son in a family with four daughters, he nevertheless impressed Kazan with his sincerity and deeply felt reminiscences of his Communist father's death in the aftermath of the Communist–centrist/rightist struggle in the Greek Civil War. Kazan later compared Giallelis' performance to that of the protagonist in Vittorio De Sica's 1949 neorealist classic Bicycle Thieves.

Giallelis worked on his English for nearly 18 months while preparing for and filming his role. He received positive critical notices. The New York Times' Bosley Crowther, in his December 16, 1963 review of the film, noted that "Greek lad Stathis Giallelis (pronounced STAH-this-Ya-lah-LEASE) is incredibly good as the determined hero, putting fire and spirit into the role". Other critics called his performance "mesmerizing", "heartbreaking" and "unforgettable".

America America earned three Oscar nominations for Elia Kazan (Best Picture, Best Director and Best Original Screenplay), but its only win on Oscar night, April 13, 1964, was for Gene Callahan's black-and-white Art Direction. Eleven additional nominations came from other awards, including Golden Globes, which, a month earlier, March 11, named Elia Kazan "Best Director" and Giallelis "Most Promising Male Newcomer/New Star of the Year", an award he shared with two of the remaining five nominees—Albert Finney and Robert Walker, Jr. He was also nominated for "Best Actor in a Drama", but lost to Sidney Poitier in his Oscar-winning Lilies of the Field role.

As America America received wide distribution in Europe and elsewhere in 1964–65, Giallelis basked in the spotlight. In the months between the end of production and its December release, he completed a cameo role in Nikos Koundouros' 1963 Greek art film Mikres Afrodites (Young Aphrodites). Returning to Hollywood, the young actor seemed to be on the verge of a long and successful film career. Ultimately, however, in the 16-year period between 1964 and 1980, he appeared in front of the camera only seven more times in widely spaced film projects, only three of which (Cast a Giant Shadow, Blue and The Children of Sanchez) were American productions.

Giallelis' first post-America America film offer came shortly after the epic went into wide release during Christmas week of 1963. Leopoldo Torre Nilsson, Argentina's internationally best known filmmaker, whose hypocrisy- and corruption-themed films regularly received acclaim at European film festivals, invited him to star in his new project, El Ojo de la Cerradura (The Eavesdropper). His co-star, and the only other non-Spanish speaker in the cast would be intense twenty-one-year-old actress Janet Margolin who, two years earlier, received critical praise for her highly dramatic co-starring role (with Keir Dullea) in Frank Perry's David and Lisa. Filmed in Buenos Aires, El Ojo de la Cerradura garnered encouraging notices at a number of film festivals and won the Silver Condor Best Film Award from the Argentine Film Critics Association. Two years later it received a belated release in U.S. art houses, including a September 1966 New York premiere. Despite good notices, it soon ended its run and has remained elusive. Giallelis' second 1966 U.S. release, Cast a Giant Shadow, is the only title in his brief filmography structured as a major studio production. The all-star epic about a Jewish-American army officer's key leadership role in winning the battles which led to the 1948 establishment of Israel, found him fifth-billed after Kirk Douglas (as the central figure, Colonel Mickey Marcus), Senta Berger, Angie Dickinson and James Donald. His role, as a dedicated Israeli fighter for independence, spotted him in various brief moments throughout the film, but did not leave a strong impression. Despite its Hollywood pedigree, Cast a Giant Shadow was shot by director Melville Shavelson entirely on outdoor locations in Israel and Italy as well as studio interiors at Rome's Cinecittà studios.

Two more years would pass before Giallelis was seen in another film. Blue was a well-budgeted independent western directed on picturesque Utah locations by Silvio Narizzano. Billed fourth after Terence Stamp (as "Azul" ["Blue" in Spanish]), Joanna Pettet and Karl Malden, Giallelis, as the son of Mexican bandit Ricardo Montalbán had little to show for his dramatic efforts and, with Montalban's "Special guest" billing factored in, he actually was, again, in fifth place. Released by Paramount on May 10, 1968, Blue was perceived by a number of critics as an anti-war allegory, specifically focusing on Vietnam. Saddled with a mostly negative response from the critics, the film was quickly out of theaters.