| Name | Operator | Began operation | Tonnage | Status |
|---|---|---|---|---|
| Maasdam | Holland America Line | 1993 | 55,451 | Operating |
| Majesty of the Seas | Royal Caribbean International | 1992 | 73,941 | Operating |
| Macau Success | Island Ship | 1974 | 9,848 | Operating. Former Omar II, Astra II, built as Golden Odyssey |
| Mandalay | Windjammer Barefoot Cruises | 1982 | 585 | Operating |
| Marco Polo | Orient Lines / Transocean Tours | 1991 | 22,181 | Operating. Former Alexandr Pushkin. |
| Marina | Oceania Cruises | 2011 | 66,084 | Operating |
| Mariner of the Seas | Royal Caribbean International | 2003 | 138,000 | Operating |
| Maxim Gorkiy | Black Sea Shipping Company Phoenix Reisen |
1974 | 24,981 GT | Ended service November 2008. Former Hanseatic, built as Hamburg. |
| Mein Schiff 1 | TUI Cruises | 2009 | 76,522 | Operating. Formerly: owned by Celebrity Cruises (1996-2009). Formerly named Galaxy, Celebrity Galaxy, Mein Schiff. |
| Mein Schiff 2 | TUI Cruises | 2011 | 77,713 | Operating. Formerly: owned by Celebrity Cruises (1997-2011). Formerly named Mercury, Celebrity Mercury. |
| Mikhail Lermontov | Black Sea Shipping Company | - | Hit a reef and sank off Picton, New Zealand in 1986 | |
| Midnatsol | Hurtigruten | 2003 | Operating | |
| Minerva | Swan Hellenic | 2008 | 12,500 | Recommenced operation for Swan Hellenic cruises after leaving Swan Hellenic in 2003 |
| Mona Lisa | Holiday Kreuzfahrten | 2002 | 27,670 | Operating. Former Kungsholm,Sea Princess,Victoria,Oceanic II |
| Monarch of the Seas | Royal Caribbean International | 1991 | 73,941 | Operating |
| Monterey | MSC Italian Cruises | 1990 | 20,046 | A Matson cruise ship constructed from a 1952 C4 Mariner-class hull formerly named Free State Mariner; renamed Monte in 2006 to be broken up for scrap in 2007 |
| MSC Armonia | MSC Italian Cruises | Post-2001 | 58,174 | Formerly: MS European Vision (2001–2004), currently operating |
| MSC Divina | MSC Italian Cruises | 2012 | 139,400 | Operating |
| MSC Fantasia | MSC Italian Cruises | 2008 | 137,936 | Operating |
| MSC Lirica | MSC Italian Cruises | 2003 | 58,825 | Operating |
| MSC Magnifica | MSC Italian Cruises | 2010 | 93,330 | Operating |
| MSC Melody | MSC Italian Cruises | 1982 | 35,143 | Operating. Formely: Atlantic, StarShip Atlantic, Melody |
| MSC Musica | MSC Italian Cruises | 2006 | 89,600 | Operating |
| MSC Opera | MSC Italian Cruises | 2004 | 58,058 | Operating |
| MSC Orchestra | MSC Italian Cruises | 2007 | 89,600 | Operating |
| MSC Poesia | MSC Italian Cruises | 2008 | 93,330 | Operating |
| MSC Sinfonia | MSC Italian Cruises | 2005 | 58,625 | Formerly: MS European Stars (2002–2004), currently operating |
| MSC Splendida | MSC Italian Cruises | 2009 | 137,936 | Operating |
Read more about this topic: List Of Cruise Ships