East Fife made it the magnificent seven at Bayview as their winning run shows no sign of stopping.
Championship club Queen's were always likely to pose the biggest test to the current streak, but the Methil side just continues to dominate in both league and cup.
It really was an excellent win at Bayview, with both the quality of the goals scored and the standard of defending so impressive.
Queen's famously boast one of Europe's most potent forwards in Stephen Dobbie and half the battle would be keeping him quiet.
The striker, excellent as he is, was barely given a kick all day and was marshalled out of the game by Ross Dunlop and Daryll Meggatt.
East Fife went into the game as underdogs from the division below but, just as they did against Partick in the previous round, proved to be more than a match for their opposition.
The first half was starting to peter out when the hosts took the lead in stunning fashion.
Queen of the South couldn't get their lines cleared properly and the ball broke to Kevin Smith on the edge of the area.
The striker quickly got the ball from out under his feet and set himself for a shot - crashing his strike high into the top corner.
Queen's started the second 45 determined to rescue their cup hopes and enjoyed their best spell of the game.
Dobbie had a goal ruled out for a foul and Meggatt threw his body on the line to block a Lyndon Dykes drive.
Gary Naysmith's side were pressing, but East Fife showed they could be a threat themselves, Scott Agnew and Smith both going close to adding another.
Boss Darren Young, celebrating his 40th birthday, threw on Jonny Court and Anton Dowds to freshen things up.
And it was to be Dowds who wrapped things up, capitalising on more slack defending from the visitors and finishing from close range.
Boss Young said: “Conditions were tricky but I thought we knocked the ball about well and scored a great goal from Kevin and then a brilliant second from Anton just chasing, getting in between and having the composure to finish.
“Defensively every single player played their part from the front to the back.
“They’re working the system well and every week the performances are getting better and better.
“There were no failures.”