| Objective, Burma! | 1945 | ★★★½ | 2 |
| Oblivion | 2013 | ★★★ | 3 |
| Observe and Report | 2009 | ★★ | 2 |
| Obsessed | 2009 | ★ | 1 |
| Ocean's Eleven | 2001 | ★★½ | 3 |
| Ocean's Thirteen | 2007 | ★★½ | 3 |
| Ocean's Twelve | 2004 | ★★½ | 3 |
| October Sky | 1999 | ★★★½ | 2 |
| Octopussy | 1983 | ★★½ | 3 |
| Oculus | 2014 | ★★½ | 3 |
| The Odd Job | 1978 | ★★½ | 3 |
| The Odd Life of Timothy Green | 2012 | ★★½ | 1 |
| Office Space | 1999 | ★★★½ | 3 |
| Of Human Bondage | 1934 | ★★½ | 3 |
| Of Love and Shadows | 1994 | ★★ | 1 |
| Oh Doctor! | 1917 | ★★½ | 3 |
| Oh, God! | 1977 | ★★★½ | 3 |
| The OH in Ohio | 2006 | ★★½ | 3 |
| The Oklahoma Kid | 1939 | ★★½ | 1 |
| Old Acquaintance | 1943 | ★★★ | 1 |
| Oldboy | 2013 | ★★ | 3 |
| Old Dogs | 2009 | ★ | 1 |
| The Old Maid | 1939 | ★★★½ | 1 |
| Old School | 2003 | ★★ | 3 |
| Olympus Has Fallen | 2013 | ★★ | 3 |
| The Omega Man | 1971 | ★★½ | 3 |
| The Omen | 2006 | ★★ | 1 |
| On a Clear Day You Can See Forever | 1970 | ★★½ | 3 |
| On Borrowed Time | 1939 | ★★★ | 3 |
| Once Upon a Honeymoon | 1942 | ★★★ | 2 |
| One A.M. | 1916 | ★★★ | 3 |
| One Day | 2011 | ★★ | 3 |
| One Eyed Jacks | 1961 | ★ | 3 |
| One Flew Over the Cuckoo's Nest | 1975 | ★★★★ | 3 |
| One for the Money | 2012 | ★★ | 3 |
| One Hour Photo | 2002 | ★★½ | 3 |
| One Million Years B.C. | 1966 | ★½ | 3 |
| One Night at McCools | 2001 | ★★★ | 2 |
| One Run Elmer | 1935 | ★★½ | 3 |
| The One That Got Away | 1957 | ★★½ | 3 |
| One Too Many | 1916 | ★★ | 3 |
| One, Two, Three | 1961 | ★★★ | 3 |
| One Way Passage | 1932 | ★★★½ | 3 |
| One Week | 1920 | ★★★★ | 3 |
| On Golden Pond | 1981 | ★★★★ | 3 |
| On Her Majesty's Secret Service | 1969 | ★★★ | 3 |
| The Onion Field | 1979 | ★★★ | 2 |
| Only Angels Have Wings | 1939 | ★★½ | 3 |
| Only the Lonely | 1991 | ★★★ | 2 |
| On the Beach | 1959 | ★★½ | 2 |
| On the Town | 1949 | ★★★½ | 3 |
| On the Waterfront | 1954 | ★★★½ | 3 |
| Oorlogsgeheimen | 2014 | ★★★½ | 1 |
| Open Season | 2006 | ★★ | 2 |
| Open Water | 2004 | ★½ | 3 |
| Operation Pacific | 1951 | ★★½ | 3 |
| Operation Petticoat | 1959 | ★★½ | 3 |
| The Opposite of Sex | 1998 | ★★★½ | 3 |
| Orca | 1977 | ★★ | 1 |
| The Order | 2003 | ★★½ | 1 |
| The Original Kings of Comedy | 2000 | ★★ | 3 |
| Original Sin | 2001 | ★★ | 3 |
| OSS 117: Cairo, Nest of Spies | 2006 | ★★★½ | 2 |
| Other Boleyn Girl | 2008 | ★★½ | 1 |
| The Other Guys | 2010 | ★★★ | 2 |
| Other Men's Women | 1931 | ★★★ | 3 |
| The Others | 2001 | ★★★½ | 3 |
| The Other Woman | 2011 | ★★½ | 1 |
| The Other Woman | 2014 | ★½ | 3 |
| Our Hospitality | 1923 | ★★★ | 3 |
| Our Idiot Brother | 2011 | ★★★ | 3 |
| Our Kind of Traitor | 2016 | ★★★ | 2 |
| Our Modern Maidens | 1929 | ★★½ | 3 |
| Out in the Dark | 2013 | ★★★ | 2 |
| The Out of Towners | 1970 | ★★★ | 1 |
| The Outsiders | 1983 | ★★ | 3 |
| Out West | 1918 | ★★½ | 3 |
| The Overnight | 2015 | ★★★ | 1 |
| Over the Fence | 1917 | ★★★ | 3 |
| Over the Hedge | 2006 | ★★★ | 3 |
| The Owl and the Pussycat | 1970 | ★★★½ | 3 |
| Oz the Great and Powerful | 2013 | ★★★ | 3 |
