O'Connell, who led the Lions in South Africa last year, hasn't played since the Six Nations defeat to Scotland due to a persistent groin injury.
The Munster second row has missed a host of crucial Heineken Cup and Magners League games for his province and has been in and out of hospital but Ireland coach Declan Kidney is hopeful he will soon be available for selection.
O'Connell is joined in the 33-man squad by a further 12 Lions, plus two players who were due to tour South Africa this time last season before injury prevented them from doing so.
Tommy Bowe, Gordon D'Arcy, Keith Earls, John Hayes, Jamie Heaslip, Rob Kearney, Donncha O'Callaghan, Brian O'Driscoll, Ronan O'Gara and David Wallace all featured for Sir Ian McGeeechan's elite last summer, while Shane Horgan and Geordan Murphy were tourists five years ago and Jerry Flannery and Tomas O'Leary were original Lions selections in April 2009.
Kidney has named three uncapped players for next month's tour Down Under that is preceded by a fixture against the Barbarians in Limerick.
Ulster's Chris Henry and Dan Tuohy and Leinster's Fergus McFadden have all won call ups but there is no place for 2009 Lions Stephen Ferris and Luke Fitzgerald or Munster's Denis Leamy who miss out through a broken cheekbone and a serious knee injuries respectively.
Ireland's summer fixtures
Ireland vs Barbarians, Friday, June 4, Thomond Park
New Zealand vs Ireland, Saturday, June 12, New Plymouth
New Zealand Maori vs Ireland, Friday June 18, Rotorua,
Australia vs Ireland, Saturday, June 26, Brisbane
Rory Best (Banbridge/Ulster)
Tommy Bowe (Ospreys)
Tony Buckley (Shannon/Munster)
Tom Court (Malone/Ulster)
Sean Cronin (Buccaneers/Connacht)
Gordon D'Arcy (Lansdowne/Leinster)
Keith Earls (Young Munster/Munster)
Jerry Flannery (Shannon/Munster)
John Hayes (Bruff/Munster)
Cian Healy (Clontarf/Leinster)
Jamie Heaslip (Naas/Leinster)
Chris Henry (Ballymena/Ulster)
Marcus Horan (Shannon/Munster)
Shane Horgan (Boyne/Leinster)
Shane Jennings (St.Mary's College/Leinster)
Robert Kearney (UCD/Leinster)
Fergus McFadden (Old Belvedere/Leinster)
Kevin McLaughlin (St.Mary's College/Leinster)
John Muldoon (Galwegians/Connacht)
Geordan Murphy (Leicester)
Donncha O'Callaghan (Cork Constitution/Munster)
Paul O'Connell (Young Munster/Munster)
Mick O'Driscoll (Cork Constitution/Munster)
Brian O'Driscoll (UCD/Leinster)
Ronan O'Gara (Cork Constitution/Munster)
Tomas O'Leary (Dolphin/Munster)
Eoin Reddan (Lansdowne/Leinster)
Jonathan Sexton (St.Mary's College/Leinster)
Peter Stringer (Shannon/Munster)
Andrew Trimble (Ballymena/Ulster)
Dan Tuohy (Ballymena/Ulster)
David Wallace (Garryowen/Munster)
Paddy Wallace (Ballymena/Ulster)
NB. Bold denotes Lion