Mark Johnson was born on June 16, 1960, in Henryetta, Oklahoma.  He grew up less than a block from the Main Street Tennis Courts in Henryetta.  His dad, C. Eugene Johnson, began tossing balls to him at the age of two and he started taking group lessons from Coach Mike Kennedy in Dr. Carlton E. Smith's Summer Tennis Program when he was just three years old.

Mark began playing tournaments at the age of six.  Competing against much older kids, he reached the finals of his first tournament in Little Rock, Arkansas.  Mark was a Junior High School State Champion in 1975.  He won the Oklahoma High School State Championship at #1 Singles in 1976 and 1977 and led Henryetta High School to the State Team Championship in 1977.  Between 1971 - 1980, he played the Missouri Valley Sectional Championship eight times.  He reached the Finals every year and won the Singles Championship five times.  He also won the Missouri Valley Sectional Doubles Championship four times.  Mark's numerous National Rankings included being ranked #3 in the Nation in Doubles in 1976.  In 1977, he was a National Prep Sports Magazine High School All-American and was invited to the United States Junior Davis Cup Camp in San Antonio, Texas.

In January of 1978, Mark graduated from Henryetta High School a semester early.  Two days after finishing High School, he began his college career at the University of Arkansas, and later that spring made history by becoming the first Arkansas player to win a Southwest Conference Singles Championship, thus completing a semester of college and winning a conference singles title before his 18th birthday.  After winning another Southwest Conference Singles Championship Title in 1979, he transferred to Oklahoma State University, where he played his final two years for Hall of Fame Coach James Wadley.  Mark won two Big 8 Conference #1 Singles Titles and two Big 8 Conference #1 Doubles Titles for OSU in 1981 and 1982.  The 1981 OSU team won the Big 8 Team Championship and Mark earned NCAA All-American honors by reaching the Quarterfinals of the NCAA Championships in Doubles.

After completing his college eligibility, Mark remained at OSU as an Assistant Coach for OSU's 1983 Big 8 Conference Championship Team.  He then worked as a Tennis Professional for five years at Quail Creek Country Club in Oklahoma City and Oak Tree Country Club in Edmond.  In 1988, Mark was hired as the Head Women's Tennis Coach at the University of Oklahoma.  During the next 20 years, his teams recorded an OU record 306 wins.  He was named the Big 8 Conference Coach of the Year in 1991, 1994, and 1995.  He was named the Big 12 Conference Coach of the year in 1999 and the Intercollegiate Tennis Association Coach of the Year in 2003.  He retired from coaching in 2008.  He has been inducted into the Missouri Valley Tennis Hall of Fame. 

Mark and former OCU tennis player Michelle Blake have been married since 1986.  They live in Norman, Oklahoma.