The first chance was created by home striker Craig Dargo, whose dipping drive was brilliantly touched wide by keeper Graeme Smith.
Moments later, the Highlanders took the lead in sensational style. Barry Wilson flighted a perfect free-kick into the area and big skipper Darren Dods volleyed into the net from the penalty spot.
On 13 minutes Dennis Wyness forced a decent save from Smith after he whizzed past Fraser Wright and drove a low shot towards the corner but was denied.
The goalkeeper was called into action again soon after when he tipped away a free-kick from John Rankin.
Killie's first opportunity arrived on 23 minutes when Gordon Greer flashed a shot over from ten yards.
Then from the visitors' first corner, on 28 minutes, Colin Nish flicked it on and Steven Naismith was on hand to bury it for the leveller.
Matters got worse for Inverness when Nish beat the offside trap and slotted the ball below Mark Brown to give Jim Jefferies' side the advantage.
The equaliser came just before the break when Smith spilled a Rankin free-kick and Dods was there to net his second.
Just when the interval approached, a penalty was awarded when a Wilson corner struck a hand in the box. Dargo then smashed home his sixth of the season for a 3-2 half-time scoreline.
The goal spree continued on 49 minutes when Paul di Giacomo delivered a cross and Nish slid it for his second strike of the day.
Inverness midfielder Ian Black then steered his header goalwards from a Rankin cross but Smith dealt with it by parrying it.
Killie stole into a 4-3 lead when Naismith bulleted home a penalty on 67 minutes when the same player was felled in the box by sub Zander Sutherland.
Dods was denied a 72nd minute hat-trick when Smith brilliantly saved his shot from a Sutherland assist.
Inverness threw on Graham Bayne for Wilson and changed to a back three in an attempt to win a point.
Dargo went close with a snapshot from distance as the hosts upped the ante. However, Killie coped with the late pressure and headed down the A9 with all three points.