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| Series Cast Summary (33 of 225) (View more cast) | Episode Count | Year Range | STARmeter™ |

| Ernie Hudson ... Warden Leo Glynn | 56 | (1997-2003) | 2,083 |

| Harold Perrineau ... Augustus Hill | 56 | (1997-2003) | 2,727 |

| Lee Tergesen ... Tobias Beecher | 56 | (1997-2003) | 3,526 |

| J.K. Simmons ... Vern Schillinger | 56 | (1997-2003) | 959 |

| Dean Winters ... Ryan O'Reily | 56 | (1997-2003) | 3,822 |

| Terry Kinney ... Tim McManus | 55 | (1997-2003) | 4,398 |

| Rita Moreno ... Sister Peter Marie Reimondo | 52 | (1997-2003) | 3,807 |
 | George Morfogen ... Bob Rebadow | 51 | (1997-2003) | 21,273 |

| Eamonn Walker ... Kareem Said | 50 | (1997-2003) | 2,484 |
 | B.D. Wong ... Father Ray Mukada | 47 | (1997-2003) | 3,549 |

| Kirk Acevedo ... Miguel Alvarez | 46 | (1997-2003) | 2,826 |
 | Philip Scozzarella ... Officer Joseph Mineo / ... | 46 | (1997-2003) | 51,875 |

| Scott William Winters ... Cyril O'Reily | 45 | (1998-2003) | 5,473 |

| Lauren Vélez ... Dr. Gloria Nathan | 42 | (1997-2003) | 1,824 |
 | Chuck Zito ... Chucky Pancamo | 41 | (1998-2003) | 13,758 |
 | Otto Sanchez ... Chico Guerra | 40 | (1998-2003) | 25,670 |

| Tom Mardirosian ... Agamemnon Busmalis | 39 | (1998-2003) | 17,904 |

| Christopher Meloni ... Chris Keller | 38 | (1998-2003) | 1,564 |
 | Granville Adams ... Zahir Arif | 37 | (1997-2003) | 41,260 |

| Craig muMs Grant ... Poet | 37 | (1997-2003) | 20,329 |
 | Carl DiMaggio ... Officer Len Lopresti / ... | 34 | (1999-2003) | 55,762 |
 | Evan Seinfeld ... Jaz Hoyt | 33 | (1998-2003) | 4,957 |

| Adewale Akinnuoye-Agbaje ... Simon Adebisi | 32 | (1997-2000) | 1,036 |

| Robert Clohessy ... Officer Sean Murphy | 32 | (1999-2003) | 15,573 |
 | Timothy L. Brown ... Officer Jason Armstrong | 32 | (1997-2003) | 118,968 |
 | Kristin Rohde ... Officer Claire Howell | 30 | (1999-2003) | 27,179 |
 | R.E. Rodgers ... James Robson | 29 | (1998-2002) | 23,631 |
 | Zeljko Ivanek ... Governor James Devlin / ... | 27 | (1997-2003) | 3,863 |

| David Zayas ... Enrique Morales | 27 | (2000-2003) | 1,433 |

| Steven Wishnoff ... Tony Masters | 27 | (1999-2003) | 53,121 |
 | Sean Dugan ... Timmy Kirk | 26 | (1998-2003) | 39,188 |

| Edie Falco ... Officer Diane Whittlesey | 23 | (1997-2000) | 2,574 |
 | J.D. Williams ... Kenny Wangler | 23 | (1997-2000) | 7,551 |
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