Hibs staged a fantastic second-half comeback to put themselves clear in third place in the league.
Tony Mowbray's young side found themselves two goals down at half-time against the run of play, but railed superbly to notch four goals of their own after the interval.
Kilmarnock started brightly, and a fine run down the right from Danny Invincibile presented a chance for Gary Wales, but Zbigniew Malkowski saved well to his right.
But Hibs failed to heed the warning and fell behind after only seven minutes to a goal from a set piece. Gary Locke swung over a corner from the left, and Simon Ford was given a free header from only six yards to give Killie the early advantage.
Hibs enjoyed the lion's share of possession but tried to over elaborate in most of their moves.
However, Alan Combe produced a stunning save low to his left to deny Garry O'Connor's close-range effort and that proved important for Killie as they went two up shortly thereafter.
Scotland star Gary Caldwell was caught in possession, and Colin Nish switched the ball into the path of Allan Johnston who produced a clinical finish, high into the net from 15 yards.
It looked as though Hibs were dead and buried, but crucially they got an early goal after the break.
Caldwell atoned for his earlier mistake when he latched on to Derek Riordan's lay-off and rifled home a low 20-yarder.
And Hibs were on level terms just after the hour when Riordan romped down the left and picked out Guillaume Beuzelin with a great cross that the Frenchman bulleted home from eight yards.
Kris Boyd had an excellent opportunity to head Kilmarnock back in front from a Hayes corner, but his effort looped over the bar and Hibs stunned Killie with two late goals to wrap up their victory.
Man-of-the-match Kevin Thomson hooked a great free-kick from the edge of the box and Beuzelin grabbed his second with a neat header from close range. Then Riordan ran on to Steven Fletcher's pass and netted with a low finish from 10 yards.
This capped a magnificent come back for a Hibs side who reaped the rewards from their more direct approach in the second half.