There is one change to the starting line-up from the side that defeated the Ospreys last weekend with Martin Moore set to make his first Heineken Cup start.
The former Leinster Under-20 captain appeared as a replacement in Swansea in place of the injured Mike Ross (hamstring) who is close to regaining full fitness.
For the round 2 fixture, Moore will start in the front row alongside experienced duo Cian Healy and Sean Cronin in a pack which is all-Ireland qualified.
Jamie Heaslip leads the team once more on the occasion of his 170th Leinster outing and he is joined in the back row by McLaughlin and last weekend's man-of-the-match Sean O'Brien.
With Brian O'Driscoll still nursing a calf injury, the province's back-line is unchanged which means that Jimmy Gopperth will make his home European debut in the number 10 jersey.
O'Driscoll's deputy at outside centre, Brendan Macken, will win his 30th Leinster cap as he continues alongside Gordon D'Arcy in midfield.
Meanwhile, Michael Bent has recovered from injury to take his place on the replacements bench alongside four other Ireland internationals.
Saturday's Leinster v Castres match is set to be a sell-out with the last remaining tickets on sale online here.
LEINSTER (v Castres Olympique): Rob Kearney; Fergus McFadden, Brendan Macken, Gordon D'Arcy, David Kearney; Jimmy Gopperth, Isaac Boss; Cian Healy, Sean Cronin, Martin Moore, Devin Toner, Mike McCarthy, Kevin McLaughlin, Sean O'Brien, Jamie Heaslip (capt).
Replacements: Aaron Dundon, Jack McGrath, Michael Bent, Quinn Roux, Rhys Ruddock, Eoin Reddan, Ian Madigan, Luke Fitzgerald.