The presenter grilled the prime minister on the ITV show on 3 May, covering topics including the cost of living crisis and the ongoing situation in Ukraine.
She even asked Johnson whether he was “honest”.
The interview earned Reid plenty of praise from viewers with some saying on Twitter that she “did a good job” and “held him to account” and one even calling it “wonderful to watch”.
However, others claimed the interview was “biased”.
Broadcasting watchdog Ofcom has confirmed that it has received 87 complaints about the 3 May instalment of the morning show.
Johnson’s interview was his first on Good Morning Britain since five years ago in 2017, when he was still the foreign secretary.
And it came four years after he seemed to hide in a fridge in order to avoid an interview on the programme.
The PM was visiting a company called The Modern Milkman in 2019 when someone from Good Morning Britain asked him if he would go on the show to talk to Reid and her former colleague Piers Morgan, who has since left the programme.
But he then appeared to disappear into an industrial fridge.
Earlier this week, it was reported that Johnson was ill with food poisoning ahead of his interview with Reid and threw up on his suit.
An aide was quoted as telling the Sunday Times: "He had food poisoning.
"He was throwing up and had to change his suit because he got sick on his lapel."
Watch: Boris Johnson asks Susanna Reid who Lorraine Kelly is