Brian McLean looked to have earned Motherwell a point with a cool finish with 10 minutes left to cancel out Danny Invincibile's opener.
But Taouil saved one of the best moments of Killie's season for the last minute with a jinking run and finish.
Motherwell must now wait until Tuesday to discover whether they have qualified for the Europa League via the Fair Play league.
The race between the St Mirren and Motherwell was "too close to call" before the game, according to the SFA, and both sides had one player booked today with Paul Quinn cautioned for the Steelmen.
With both sides assured of their places in the SPL, each manager made several changes.
Mark McGhee handed a debut to on-loan Birmingham goalkeeper Artur Krysiak with Graeme Smith on the bench in what is expected to be his final afternoon on Motherwell duty.
Kilmarnock made seven changes as Jim Jefferies left out players at risk of suspension and rested Kevin Kyle, who needed a painkilling injection to play against Inverness last weekend, when he netted his seventh goal in four games to keep Killie in the SPL.
Jefferies brought in youngsters Iain Flannigan and goalkeeper Cameron Bell, who like Krysiak, did not have a save to make in the first quarter.
Kilmarnock had to make two more changes in the first quarter as Grant Murray and Manuel Pascali went off following a clash of heads, with Gavin Skelton and James Fowler coming on.
Motherwell striker Cillian Sheridan should have tested Bell in the 18th minute but shot well over from 16 yards after being set up by David Clarkson, but the visitors took the lead on the counter attack as Taouil fed the unmarked Invincibile to power home from 12 yards.
The only time Motherwell threatened an equaliser before the break was when Clarkson headed Hammell's near-post corner across the face of goal.
Maros Klimpl lasted less than two minutes of the second period before being injured in the process of shooting.
The on-loan Slovakian midfielder was given a standing ovation as he left the field for what could be his last Motherwell game, unless he comes to an agreement with Danish club FC Midtjylland to stay long term.
The injury to Klimpl, who has been booked nine times in 2009, may have had a silver lining even though replacement Bob Malcolm, making his first appearance since December and his last in a Motherwell shirt, took less than 60 seconds to commit his first foul.
Well almost levelled in the 55th minute when McLean glanced Jim O'Brien's corner on to the bar before Invincibile sliced wide from 18 yards.
Killie were forced into their third change when Ryan O'Leary came on after David Lilley fell badly and appeared to suffer concussion and a wrist injury.
Another O'Brien corner almost created an equaliser but Sheridan glanced wide of the far post and the on-loan Celtic striker was soon denied at point-blank range by Bell as he tried to turn home a Stephen Hughes shot.
Quinn was booked by Steven Nicholls, who was taking charge of his first SPL game, after kicking the ball at a grounded Tim Clancy in the 77th minute. The full-back could have no complaints, after being warned moments earlier following a confrontation with Taouil.
Defender McLean levelled in the 80th minute with a composed first-time finish with his left foot after Clarkson got to the bye-line and cut the ball back.
The injuries kept coming - Malcolm limped off and both O'Leary and Flannigan toiled badly in the closing stages.
Taouil sent the excitable away support into raptures in the final minute with a superb winner. Fernandez back-heeled the ball into Taouil's path and the Moroccan worked his way along the bye-line with the aid of several stepovers before firing inside Krysiak's near post.