McLaughlin, whose last outing for Leinster was seven months ago, underwent surgery on his knee and shoulder in the summer and has steadily been working his way back to fitness.
Head coach Joe Schmidt has opted to make eight changes in personnel to the team that started last Monday's 30-13 victory over Ulster in Belfast.
Three of those are in the back-line as Paul O'Donohoe joins Shaun Berne at half-back, and Andrew Conway and Eoin O'Malley come in for Shane Horgan and Brian O'Driscoll on the right wing and at outside centre respectively.
Heinke van der Merwe holds onto the loosehead spot as Richardt Strauss and Clint Newland complete the front row, and Scotland international Nathan Hines returns in the second row alongside Devin Toner.
Sean O'Brien, the two-try hero against Ulster, stays at number 8 in a back row which is topped off by McLaughlin and stand-in skipper Jennings.
Stephen Keogh, who has impressed for the province's 'A' team this season, joins Eoin Reddan and Mike Ross on a replacements bench which contains both youth and experience.
Young hooker Tom Sexton, who is a member of the Leinster Academy, is standing by to make his senior debut for the province.
Meanwhile, over 16,500 tickets have now been sold for Saturday's game. Tickets will be on sale at the gate and are available to purchase online here, and from Spar (Donnybrook), the Leinster Rugby Store (Donnybrook) and Ticketmaster outlets nationwide.
LEINSTER (v Connacht): Isa Nacewa; Andrew Conway, Eoin O'Malley, Fergus McFadden, David Kearney; Shaun Berne, Paul O'Donohoe; Heinke van der Merwe, Richardt Strauss, Clint Newland, Nathan Hines, Devin Toner, Kevin McLaughlin, Shane Jennings (capt), Sean O'Brien.
Replacements: Tom Sexton, Jack McGrath, Mike Ross, Ed O'Donoghue, Stephen Keogh, Eoin Reddan, Ian Madigan, Niall Morris.