The actor, who plays Chief of Police Jim Hopper in the hit Netflix series, brought the house down with his passionate acceptance speech last night.
Taking to the stage, he looked as though he was about to break down as he delivered one of the most inspiring monologues of the ceremony.
Clutching onto the award, he told the crowd: "On behalf of this fearless and talented cast we'd like to thank Netflix."
David continued: "I would just like to say that in light of all that is going on in the world today, it is difficult to celebrate the already celebrated Stranger Things.
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David Harbour brought the house down with his passionate speech
The cast took home the trophy for best ensemble in a drama series
We repel bullies, we will shelter freaks, outcasts and those who have no home
Stranger Things star David Harbour
"But, this award from you, who take your craft so seriously and earnestly believe, like me, that great acting can change the world, is a call to arms to our fellow craftsmen and women to go deeper.
"And, through our art, to battle against fear, self-centredness and exclusivity of our predominantly narcissistic culture, and through our craft, to create more empathetic and understanding society by revealing intimate truths that serve as a forceful remind to folks that when they feel broken and tired, they are not alone."
Fellow cast mate Winona Ryder, who plays Joyce Byers in the sci-fi drama, cheered him on as he added: "As we act in the continuing narrative of Stranger Things, we 1983 midwesterners will repel bullies, we will shelter freaks and outcasts and, those who have no home.
Millie Bobby Brown was nominated for Outstanding Performance by a Female Actor in a Drama Series
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"We will get past the lies, we will hunt monsters and, when we are at a loss amidst the hypocrisy and casual violence of certain individuals and institutions we will as per Chief Jim Hopper punch some people in the face.
"We will do it all with soul and heart and joy."
As David concluded his speech the audience got to their feet and cheered him on as the Stranger Things cast jumped around on stage in celebration.
The Crown's Claire Foy dedicated her award to co-star Matt Smith
Millie Bobby Brown, who stars as Eleven, was also nominated for Outstanding Performance by a Female Actor in a Drama Series.
Unfortunately for the youngster, she lost out to Claire Foy, who took home the trophy for her portrayal of Queen Elizabeth II in Netflix series The Crown.