Kilmarnock striker Colin Nish scored the goal that earned his side all three points at Fir Park.
Nish (left) celebrates with Craig Dargo
Motherwell had numerous chances to score themselves, but they failed to take any of those.
Nish's vital goal came in 58 minutes following Danny Invincibile's dangerous cross into the box.
Gordon Marshall initially denied Craig Dargo, but the ball broke to Nish and all that was required was for him to stab the ball home from close range.
The home side started well and Scott McDonald surged into the opposition box almost straight from the kick-off, but Kilmarnock goalkeeper Alan Combe tipped his shot just past the upright.
Motherwell should have found themselves behind after 20 minutes when Allan Johnston released Dargo into the box, but he somehow managed to hit the post when it looked easier to score.
McDonald threatened the Kilmarnock goal again at the beginning of the second half when he collected Jim Paterson's pass just outside the six-yard box before producing a delightful flick but the effort would not drop in time.
Kilmarnock may not have enjoyed the quantity of goalscoring opportunities
produced by Motherwell but they scored what proved to be the only goal of the game after 58 minutes.
Invincibile's cross sparked mayhem and though Marshall pounced off his line to deny Dargo, the ball broke to Nish and he scored a simple goal.
Motherwell could have grabbed a late equaliser when Paul Quinn robbed Combe of
possession a few yards out.
But he could not make it count and the ball was eventually hooked to safety
as Kilmarnock held on for the three points.
Motherwell: Marshall, Corrigan, Craigan, Partridge, Hammell,
Foran, Leitch (Fagan 53), Paul Quinn, Paterson,
Scott McDonald (Burns 73), Clarkson.
Subs Not Used: Corr, Cowan, Fitzpatrick, Connolly, Coakley.
Booked: Clarkson, Hammell, Paterson.
Kilmarnock: Combe, Lilley, Greer, Dindeleux, Leven,
Johnston (Murray 63), McDonald, Ford, Invincibile, Nish,
Dargo (Fowler 87).
Subs Not Used: Hay, Smith, Joly, Canning, Naismith.
Booked: Greer, Lilley.
Goal: Nish 57.
Ref: C Murray