Murphy opened with a break of 99, but was never really in the running to reach the final of the tournament he won in 2008 as runs of 55, 83, 58 and 51 carried world number one Selby into a final against tournament favourite O'Sullivan, or former finalist Fu over the best of 19 frames on Sunday.
O'Sullivan and Hong Kong's Fu play the second semi-final from 7pm (GMT) on Saturday night at York's Barbican Centre.
Selby: O'Sullivan snooker's greatest player, but critics inspire me when I meet him
Selby won the 2012 final against Murphy 10-6, and was equally dominant in this last four meeting.
He led 3-1 before a 57 from Murphy saw the deficit reduced to 3-2 before running out a comfortable winner.
Mark Selby breezes into third UK final
"I could not have started better and it was the best I felt all week, but the mistakes against Mark are magnified so much," said Murphy.
"If you don't kill him off, he has a way of getting himself back in the match. He is so difficult to crack."
But Leicester's Selby - who lost 10-7 to Neil Robertson in the 2013 UK final - pinched a tight seventh frame before pulling away in the eighth to secure a deserved progress over two hours and 40 minutes.
Selby defeats O'Sullivan 10-7 to win UK Championship
Mark Selby 10-7 Ronnie O'Sullivan: Frame-by-frame