Fu actually lost the first two frames of the match and was 56-0 down in the third before a break of 80 saw him nick that frame and from then on he never looked back.
In three of the final four frames Murphy wouldn't even pot a ball as Fu flew away to take the victory.
A run of 61 helped the Hong Kong potter make it 2-2 and then a break of 70 in the fifth edged him in front.
Murphy did score 13 points in the next frame but Fu still took it with two mini-breaks and a fine 115 in the next saw him secure the match.
Fu will play Dominic Dale in the quarter-finals.
Defending champion Barry Hawkins is also out after he crashed to Tom Ford 5-4.
The final frame was a nail-biter with both players fouling four times.
There were no problems for world number one Mark Selby though as breaks of 69, 71, 76 and 90 helped him to a 5-1 win over Zhang Anda.
There were also victories for Robert Milkins, Joe Perry and Mark Davis over Rory McLeod, Stuart Bingham and Alfie Burden respectively.
Thursday results (all second round)
Marco Fu 5-2 Shaun Murphy
Joe Perry 5-3 Stuart Bingham
Tom Ford 5-4 Barry Hawkins
Robert Milkins 5-2 Rory McLeod
Mark Davis 5-3 Alfie Burden
Mark Selby 5-1 Zhang Anda