The theme song to MacGyver was composed by Randy Edelman, an American film and television score composer. He is now 62 years old.
As far as I can tell, there were slight variations on the instrumentation of the song from its debut until the 7th and final season. The clips used changed for sure; luckily, some dude uploaded all the intros to each of the 7 seasons in YouTube.
Additional
Question: What is MacGyver’s first name?
Answer: Menemis, as in “Menemis, MacGyver.” Kidding, his first name is Angus; he was played by actor Richard Dean Anderson.
Two MacGyver television movies entitled MacGyver: Lost Treasure of Atlantis and MacGyver: Trail to Doomsday, were aired on ABC in 1994.
Watch & Listen
Below is the intro to season 1, which was taken from the YouTube link above.