Lawrence "Larry" W. Obsitnik was born in Little Rock on December 27, 1919. He attended Little Rock schools. A boyhood interest in photography included the opportunity in 1928 to take pictures of presidential candidate Herbert Hoover in Joliet, Illinois. Graduating from high school as war clouds gathered in Europe, Obsitnik joined the Arkansas National Guard.

Because of Obsitnik's interest in and experience with photography he was assigned to the Signal Corps Photographic Center on Long Island, New York for training as a news and combat photographer. On January 6, 1941, he was inducted into federal service as a corporal in Battery A, 206 Coast Artillery (AA). In June 1941 his unit was transferred to Dutch Harbor in the Aleutian Islands. He was at nearby Morris Cove when the Japanese attacked Dutch Harbor in early June 1942. In May 1943 he was transferred to the photographic detachment of the 14th Signal Corps Service Company at Fort Richardson, Alaska.

After the war Little Rock photographer William Hughes hired Obsitnik as an assistant. Through Hughes he received an opportunity to photograph Arkansas Razorback coach John Barnhill during a football game for the Arkansas Gazette. The photographs, featured on the newspaper's front page, created a sensation, and in 1949 Obsitnik became the Gazette's first full-time photographer. For the next thirty-five years he worked for the newspaper, becoming known as "the Chief."

Obsitnik's use of unusual camera angles and poses revolutionized photojournalism in Arkansas. During his career he photographed every United States president from Harry Truman to Ronald Reagan. He also photographed Arkansas politicians, public figures, and numerous celebrities. His 1957 photograph of American paratroopers entering Little Rock against the backdrop of a billboard reading "Who will build Arkansas if her own people do not?," taken during the Little Rock Central desegregation crisis, earned him a Pulitzer Prize nomination.

During his life, Obsitnik married three times. By his first wife he had one son and four daughters. His last wife, Nina Obsitnik, survived him. He died on November 9, 1984.