Lansbury, Martin and Tosi will receive Honorary Awards. Angelina Jolie will receive the Jean Hersholt Humanitarian Award.
Lansbury has received three Academy Award nominations for her supporting performances on film. She also did voice work for the first animated feature to receive a Best Picture nomination, "Beauty and the Beast."
Martin, who got his start in television, is a versatile actor, writer, comedian and musician. He is a three-time host of the Oscars, most recently in 2010 with Alec Baldwin.
Costume designer Tosi rose to prominence through his collaborations with Italian director Luchino Visconti on such films as "White Nights" and "Rocco and His Brothers." Tosi received nominations for his designs for "La Cage aux Folles" and "La Traviata."
Jolie, who won an Oscar for her supporting performance in "Girl, Interrupted," has been an impassioned advocate for humanitarian causes, traveling widely to promote organizations and social justice efforts. Her dedication to these causes has also shaped her work in films that tackle global humanitarian issues including "A Mighty Heart" and her feature film directorial debut "In the Land of Blood and Honey."
The Honorary Award, an Oscar statuette, is given "to honor extraordinary distinction in lifetime achievement, exceptional contributions to the state of motion picture arts and sciences, or for outstanding service to the Academy."
The Jean Hersholt Humanitarian Award, also an Oscar statuette, is given "to an individual in the motion picture industry whose humanitarian efforts have brought credit to the industry."
"The Governors Awards pay tribute to individuals who've made indelible contributions in their respective fields," said Academy President Cheryl Boone Isaacs.