Lord Alan Sugar lost patience with the father-of-two after he led the boys' team to defeat in a sausage selling challenge.
The boys' Team Synergy made a profit of £305.90 selling their budget bangers in West London, but were edged out in the boardroom showdown by the girls' Team Apollo, who earned £321.16 with their gourmet sausage sales.
Harris passionately defended his performance as leader in the task, insisting that he was a "very accomplished salesperson", despite bringing in less than £20 himself.
He brought telecommunications entrepreneur Stuart Baggs and unemployed Alex Epstein back into the boardroom. Epstein was criticised for taking a back seat on the challenge and his faults in the sausage production. Defending himself, the former corporate communications worker said: "It takes a sausage maker many years before they get it right every time."
Baggs was criticised by Sugar and Karren Brady for exaggerating his sales on the task and his aggressive pitching to customers.
However, ultimately, it was Harris's poor reception from his teammates that cost him the job with Sugar. Every member of the team criticised his performance and Shibby Robati suggested that he may have been "out of his depth".
Recently graduated student Raleigh Addington pleaded with Sugar to fire the project manager, explaining: "I was let down yesterday by a team leader who was like a bull in a china shop. He crashes into people, he was so thuggish with other members of his team. He just shouts at us. He was always looking over my shoulder. It wasn't fair... it was shameful."
After giving his summary of all three candidates, Sugar said: "The failure of this task in this particular case was the team leader. You had your chance. You blew it. Dan... you're fired."
He also revealed to Brady and Nick Hewer that he was very close to firing Baggs in a double elimination, confiding: "This young lad Stuart is a handful. I was close to firing two of them today. I ain't putting up with him much longer."
Of his early exit from the show, Harris said in the infamous black cab: "Unfortunately, we lost the task and as project manager I knew if it went wrong, I would be in the firing line. I'm not happy, but it's my responsibility."
The Apprentice continues next Wednesday at 9pm on BBC One.