The highlight of Garrison's career took place at Wimbledon in 1990 where she defeated the French Open champion Monica Seles in the quarterfinals and the Wimbledon champion and World No. 1 Steffi Graf in the semifinals. During her career, Zina won 14 top-level singles titles and 20 doubles titles.

Garrison turned professional in 1982, enjoying notable success on-court. During her first full year on tour, she reached the Australian Open semifinals and finished 1983 ranked as the World No. 10.  In 1984, she won her first top-level singles titles at the European Indoor Championships. In 1985, Zina was a Wimbledon semifinalist and in 1986 she won her first tour doubles at the Canadian Open.

At the Australian Open of 1987, Garrison won the mixed doubles and finished runner-up in the women's doubles. At the 1988 Olympic Games, Garrison partnered up with Pam Shriver, winning the women's doubles Gold Medal for the United States. Shriver was later defeated by Garrison in the quarterfinals of the singles event, earning Zina a Bronze Medal. In 1989, Garrison defeated Evert in the quarterfinals of the US Open. Garrison finished 1989 ranked as World No. 4 in singles.

At the age of ten, Zina Garrison started playing tennis. She entered her first tournament at the age of 12 and two years later she won the national girls' 18s title. In 1981, Zina won the Wimbledon and the US Open junior titles, ranking as the World No. 1 junior player. In 1996, she retired from the professional tour. She has since worked as a TV commentator and has maintained active roles in the community as well as in tennis. 

In 1988, she founded the Zina Garrison Foundation for the Homeless, and in 1992 she founded the Zina Garrison All-Court Tennis Program, supporting inner-city tennis in Houston, Texas. Garrison has also served as a member of the U.S. President's Council on Physical Fitness and Sports.