The opener was a sign of things to come when Killie skipper Garry Hay's inswinging corner was allowed to find the net through a packed six-yard box.
The Pars were level within four minutes when Stevie Crawford was left free six yards out to tap Owen Morrison's cross home.
Killie regained the lead in the 19th minute with a superb goal. Hay played a sumptuous one-two with Steven Naismith. He was entitled to finish himself, but unselfishly squared to Paul di Giacomo.
Di Giacomo made it 3-1 in the 25th minute when goalkeeper Graeme Smith's punt was missed by the Pars defence and his 30-yarder beat Dorus de Vries.
Incredibly, Killie had a fourth goal before the half-hour mark. Scott Wilson's crazy foul on Colin Nish gave Hay the chance to deliver another telling cross which Frazer Wright powered goalwards. De Vries produced an excellent block, but Nish was on hand to knock the ball home.
Substitute Souleymane Bamba was brought on to steady the Pars ship, but lashed out at Naismith in the 57th minute and was sent off, before Nish added a fifth against his former club.