Jon Morris was born on April 5, 1942 in Washington, DC. and was a three-sport athlete in football, basketball and baseball at Gonzaga College High School in Washington, DC.

After high school he played center and linebacker for three seasons at Holy Cross, where he was a  Holy Cross Varsity Club Athlete of the Year and Lineman of the Year in 1963. He was selected All-East and All-America in his senior year, played in the College All-Star Game and captained the Senior Bowl

The Green Bay Packers, coached by Vince Lombardi, picked Morris as their number two draft choice, however Morris chose to go with the Boston Patriots instead and he was signed on as their third pick.

He was the Patriots' team Rookie of the Year in 1964, and their "Unsung Hero" in 1965. He was an AFL All-Star six times, 1964 through 1969, and was an AFC Pro Bowl Center in 1970. He is 2nd to John Hannah for the most appearances by a Patriot player in a League All Star Game or Pro Bowl Game. He played 128 games for the Patriots, the eighth best individual record in club history.

Morris recovered several fumbles during his career. The first was a fumble by running back Ron Burton in the Boston Patriots' 24-7 victory over the Kansas City Chiefs at Fenway Park on October 23, 1964. In 1966, he recovered a fumble by running back Larry Garron in the Patriots' 27-27 tie with the Kansas City Chiefs at Municipal Stadium on November 20. He also recovered a fumble by fullback Jim Nance in the Patriots' 16-0 loss to the Houston Oilers at Fenway Park on October 13, 1968. 

After his playing career, Morris worked as the color commentator on Patriots radio broadcasts from 1979 to 1987, followed by color analysis of NFL games for NBC television. 

Jon Morris was inducted into the Holy Cross Hall of Fame in 1973. and was named to the second team, All-Time All-AFL Team. He selected Boston Patriots All-1960s Team and selected by a senior selection committee as a member of the Patriots Hall of Fame in 2011.