Mackey was born in Gladewater, Texas and lived part of his life in Apline, Texas when his father was a high school coach after leaving the NFL. His family moved back to East Texas before his high school years. As a student (at Spring Hill High School in Longview, Texas) he set multiple passing records and was selected to the all-state team in both his Junior and Senior years. Mackey accepted an athletic scholarship to Texas A&M-Commerce (then East Texas State University) where he was to play both Football and Basketball.
Mackey played for the Texas A&M-Commerce Lions from 1980-1983. He backed up All-American and future All-Pro Wade Wilson his freshman season, a season in which Wilson and Lions won their Conference and were national semi-finalists. Mackey took over at the starting spot his sophomore year. He led the Lions to a 7-4 record and a fifth place finish in the Lone Star Conference, throwing for 2.074 yards and 18 touchdowns. As a Junior he threw for 1,667 yards and 11 touchdowns and led the Lions to a 6-4 record, good enough for LSC conference runner-up (2nd place). As a Senior, he led the 1983 Lions to a Lone Star Conference Championship with an 8-2 record, throwing for 1,960 yards and 14 touchdowns. He was known as an athletic roll-out passer who was a dual threat as a passer and a runner.
In his two-year National Football League career as a backup quarterback for the New York Jets and the Miami Dolphins, Mackey passed for 729 yards and 3 touchdowns, rushed for 563 yards, and threw 6 interceptions.
Kyle Mackey ended his Arena Football League career completing 187 of 346 passes attempted (54.0% of passes completed), 2,253 passing yards, 34 touchdowns, only 14 interceptions and a quarterback rating of 81.96.