Peacock, who retired from international rugby league last July, was expected to take up a support role with England coach Steve McNamara this year. But the Leeds Rhinos forward, who turned 35 last month, has told McNamara he does not feel able to devote enough time to the national team.
"I'm doing a masters in sports business and administration and that's taking up too much of my time," Peacock told reporters at the Leeds pre-season media day.
"With playing as well and having three kids, I'd rather do two or three jobs well than four averagely.
"If I was to commit to doing the England job, I wouldn't have the time to do all four jobs properly.
"I think Steve kind of suspected it might be coming. He totally understands about chewing off too much.
"They will get somebody else to do that role. Steve said if he needs any advice he'll ring me but I don't imagine he will. He'll be fine with all the staff he's got at the moment."
Peacock is doing his masters at Leeds Metropolitan University alongside club-mate Kevin Sinfield, his successor as England captain, with both men planning to remain involved in the game in an administrative capacity when they retire.