In an interview with the Radio Times, Colonel Tim Collins said that next week's episode of Accused "abjectly fails the responsibility test".
The episode will see two friends join the armed forces, and subsequently face bullying and intimidation from a superior officer.
Col Collins blasted the instalment's "gratuitous violence" and "foul and abusive language".
He said: "Having served in the British army for 23 years, I can unequivocally say this has absolutely no basis in reality.
"There is no point to Accused except to try to shock."
McGovern responded to the comments, saying that he has "the greatest respect" for British soldiers.
He stressed that the drama is "a work of fiction", adding: "As a dramatist I was interested in exploring how soldiers have to be at a certain mindset to kill."