Robert Lewis Bell was born on January 18, 1922 in Flint, Michigan. His father was an assembly worker at General Motors and his mother was a housewife. He had two older brothers. After graduating high school, a friend's family offered to take him along to Arizona, where he dug ditches, worked as a carhop and lumberjack, and signed onto construction jobs. His show business career began as a U.S. Cavalryman extra for the motion picture Arizona (1940), where he also helped build the village of "Old Tucson" for the movie.

Although he was certifiably blind in his right eye, he succeeded in passing the Marine Corps physical in 1941, by memorizing the eye charts. Less than a year later, however, he was given a medical discharge but decided to try again, only this time, with the Navy. With the help of a sympathetic Navy doctor, he was accepted and served in San Francisco and, later, the Philippines, until 1946.

Upon his discharge, he returned to Flint, where he joined a community theater production and was subsequently offered a job as an announcer and disc jockey at WMRP Radio. A year later, he moved to South Bend, Indiana's WHOT Radio where he met and married copywriter Carol Atkinson. In 1950, they moved to Indianapolis, where he broke into television on WFBM-TV.

Bell's flair for comedic character acting surfaced in 1953, when he was paired with variety/talk show host Wally Phillips at WLWT-TV and WLW Radio in Cincinnati, Ohio. In 1956, the stations' Executive Vice President, Ward Quaal, left the company to become General Manager of WGN Continental Broadcasting Company (WGN-TV & Radio) in Chicago and brought Bell, Phillips and the show's writer/director/producer Don Sandburg along. During the four years that followed, Phillips and Bell starred on their own variety series, which included "The Wally Phillips Show" and "Midnight Ticker". Bell also doubled as a staff announcer. From 1959 until 1968, he hosted "The Three Stooges" weekday afternoon showcase as "Andy Starr", the elderly custodian of the Odeon Theater. But it was in 1960 when WGN-TV asked him to portray the character that would make him a Chicago television legend, "Bozo the Clown".

Alan Livingston created "Bozo" for Capitol Records in Hollywood, California in 1946. He hired voice artist and former circus clown, 'Pinto Colvig', to portray the character on the recordings and first Bozo television series, "Bozo's Circus", on KTTV-TV in Los Angeles in 1949. In the late 1950s, Livingston and Capitol briefly parted ways and sold the licensing rights to Larry Harmon, whose business partner, Jayark Films Corporation, began distributing Bozo limited-animation cartoons to television stations along with the rights for each to hire its own live Bozo host.

Chicago's Bozo debuted on June 20, 1960 starring Bob Bell on a live 30-minute "Bozo" show weekdays at noon, performing comedy sketches and introducing Bozo cartoons. The program was placed on hiatus in January 1961 to facilitate WGN-TV and Radio's move from Tribune Tower in downtown Chicago to the city's northwest side. The show was expanded to an hour and returned as "Bozo's Circus" on September 11, 1961 with additional cast members, a 13-piece orchestra, comedy sketches, circus acts, cartoons, games and prizes before a 200+ member studio audience. The show and Bell's portrayal achieved a popularity and success unlike any locally produced children's show in the history of television. His improvisational skills on live television, double-entendres and Jackie Gleason-like mannerisms also attracted a huge adult following. The program began airing nationally via cable and satellite in 1978, and studio audience reservations surpassed a 10-year wait. In 1980, the series moved to weekday mornings as "The Bozo Show" and aired on tape delay.

Bell retired in 1984 with the show remaining #1 in its timeslot. Immediately following his retirement, the Chicago Chapter of the National Academy of Television Arts and Sciences Board of Directors honored him with their Governors' Award. Fellow cast members throughout his 24-year run as Bozo included Ned Locke as Ringmaster Ned, Bob Trendler as Mr. Bob, Don Sandburg as Sandy the Tramp, Ray Rayner as Oliver O. Oliver, Roy Brown as Cooky the Cook, Marshall Brodien as Wizzo the Wizard, and Frazier Thomas. Joey D'Auria took over the Bozo role until 2001.

After raising four children, Bell and his wife Carol moved from Deerfield, Illinois to Lake San Marcos, California, an area he had visited while serving in the Marine Corps during World War II. In addition to presiding over the Kiwanis Club of Lake San Marcos, he served on the board of directors of a community educational association that raised funds for the local school system.

In 1986, he was greeted with a lengthy standing ovation when he returned for a special guest appearance as himself during a live broadcast of "The Bozo 25th Anniversary Special" from Medinah Temple in Chicago. Ten years later, he became the first portrayer of Bozo to be inducted into the International Clown Hall of Fame in Wisconsin.

On December 8, 1997, Bob Bell passed away due to heart failure at the age of 75 in San Marcos, California. Illinois Governor Jim Edgar and Chicago Mayor Richard M. Daley proclaimed April 18, 1998 "Bob Bell Day" in the State of Illinois and City of Chicago as Addison Street near the WGN-TV Studios was named "Bob Bell Way." In 1999, actor and Chicago native Dan Castellaneta, best known as the voice of Homer Simpson and Krusty the Clown on "The Simpsons" television series, revealed during a national television interview that his voice characterization of Krusty was based on Bob Bell's Bozo. Considering Bell's sly sense of humor, there's no doubt he would be proud.