Jean Pierre Lux and Derek McGrath from tournament organisers ERC performed the draw on Tuesday morning at the Aviva Stadium in Dublin, with Tigers ranked in the second tier of clubs.
Two-time winners Tigers will meet Toulouse for the first time since 2007/08, while Ospreys have been pool opponents three times and Treviso four times in recent seasons.
The 2013 Heineken Cup Final is at the Aviva Stadium on Saturday, May 18.
2012/13 Heineken Cup pools
Pool 1 – Munster Rugby, Edinburgh Rugby, Saracens, Racing Metro
Pool 2 – Toulouse, Leicester Tigers, Ospreys, Benetton Treviso
Pool 3 – Biarritz Olympique, Harlequins, Connacht, Zebre
Pool 4 – Northampton Saints, Ulster Rugby, Glasgow, Castres,
Pool 5 – Leinster Rugby, ASM Clermont Auvergne, Scarlets, Exeter Chiefs
Pool 6 – Cardiff Blues, Toulon, Sale Sharks, Montpellier
Heineken Cup and Dates 2012/13
Round 1 – October 11/12/13/14
Round 2 – October 18/19/20/21
Round 3 – December 6/7/8/9
Round 4 – December 13/14/15/16
Round 5 – January 10/11/12/13
Round 6 – January 17/18/19/20
Quarter-finals – April 4/5/6/7
Semi-finals – April 26/27/28
Final – May 18
