The Blues made a bright start at Stade Felix Mayol and surged into an 8-0 lead thanks to Leigh Halfpenny's early try.
But Toulon fought back and ran riot with seven tries through Rudi Wulf, Xavier Chiocci, Jean-Charles Orioli, Maxi Mermoz, Alexis Palisson, Mathieu Bastareaud and Florian Fresia.
The bonus-point victory sees Toulon restore their five-point lead at the top of Pool Six and while they are already through, they can secure a home quarter-final in next week's trip to Montpellier.
The Blues fought back with tries from Alex Cuthbert, Dafydd Hewitt and Halfpenny but it was a mere consolation.
Phil Davies welcomed the Wales duo back into the starting line-up following injury but Jason Tovey was left in the doghouse.
The fly-half-cum-full-back was set to face the French giants but was unable to travel after his pet Labrador Buster ate his passport.
The Welsh region were also without Bradley Davies, who stayed at home for the birth of his first daughter Elle Cheryl Davies, but has also suffered a serious ankle injury that is likely to end his Six Nations hopes. And they were dealt a further blow when Gavin Evans was forced to withdraw due to a back spasm.
Jonny Wilkinson led Toulon but it was Halfpenny opened the scoring after less than a minute as Pierrick Gunther was penalised for failing to release.
And the Blues continued to build momentum with a bright start. They stretched their lead to eight points midway through the half as the full-back scampered into the corner.
Sam Warburton flung the ball out from a retreating scrum but Owen Williams hit a sublime line off Jamie Roberts to slice through Toulon.
He evaded Palisson before drawing Mermoz to put Halfpenny away.
But Toulon instantly responded, winning the ball from the restart and launching a sustained period of pressure.
Chris Masoe evaded Roberts and although hauled down the ball was recycled for Wilkinson to send Wulf over the whitewash.
Wilkinson slotted the conversion to close the gap to one point and within minutes Toulon surged in front.
After opting to kick to the corner Toulon launched a rolling maul, Cardiff initially held them at bay but following several forward drives, Chiocci burrowed over.
Toulon were relentless in their assault and following another forward orientated attack the ball was spread blind for Orioli to dive over.
It took Toulon just four minutes of the second half to clinch the bonus point. Rhys Patchell missed touch and Toulon hit on the counter-attack. The ball was spread through hands and Delon Armitage threaded through a grubber kick that Mermoz collected to score.
They continued to run riot with Bastareaud offloading to Palisson, who danced past Halfpenny to score Toulon's fifth.
Bastareaud was next to cross the whitewash after bulldozing over following a neat switch with Wulf.
That led to Bernard Laporte ringing the changes but it did not affect their attacking intent with Steffon Armitage making the initial inroads for Fresia to power over.
To their credit the Blues continued to battle and a break from the Williams laid the platform for Cuthbert to squeeze into the corner.
And they continued their late rally with further tries from Hewitt and Halfpenny to claim a bonus point of their own.
- Sports & Recreation
- Leigh Halfpenny
- Alexis Palisson
- Mathieu Bastareaud