M-N
| Title | Director | Cast | Genre | Notes |
|---|---|---|---|---|
| The Man from Dakota | Leslie Fenton | Wallace Beery, Dolores del Río | Historical Drama | |
| The Marines Fly High | Benjamin Stoloff, George Nichols Jr. | Richard Dix, Chester Morris Lucille Ball | Adventure Drama | |
| The Mark of Zorro | Rouben Mamoulian | Tyrone Power, Linda Darnell, Basil Rathbone | Adventure | Nominated for Academy Award. Footage preserved in US National Registry. |
| Melody Ranch | Joseph Santley | Gene Autry | Western | |
| Mexican Spitfire | Leslie Goodwins | Lupe Vélez, Leon Errol | Comedy | |
| The Milky Way | Rudolf Ising | Bernice Hansen | Animated Short | Won Academy Award. |
| The Mortal Storm | Frank Borzage | James Stewart, Robert Young | Propaganda | |
| Mr. Duck Steps Out | Jack King | Animated Short | ||
| The Mummy's Hand | Christy Cabanne | Dick Foran | Horror | |
| Music in My Heart | Joseph Santley | Tony Martin, Rita Hayworth, Edith Fellows | Musical | Nominated for Academy Award. |
| My Favorite Wife | Garson Kanin | Irene Dunne, Cary Grant, Randolph Scott | Screwball comedy | Nominated for 3 Academy Awards. #18 in Top Grossing Films. |
| My Little Chickadee | Edward F. Cline | W. C. Fields | Comedy | |
| My Son, My Son! | Charles Vidor | Madeleine Carroll, Brian Aherne, Louis Hayward | Drama | Nominated for Academy Award. |
| Mysterious Doctor Satan | William Witney, John English | Action Adventure | ||
| New Moon | Jack Conway | Jeanette MacDonald, Nelson Eddy | Musical Drama | |
| A Night at Earl Carroll's | Kurt Neumann | Ken Murray, Lillian Cornell, J. Carrol Naish, Rose Hobart | Musical | |
| No Census, No Feeling | Del Lord | The Three Stooges | Comedy Short | |
| North West Mounted Police | Cecil B. DeMille | Gary Cooper, Madeleine Carroll, Paulette Goddard | Western | Won Academy Award; another 4 nominations. |
| Northwest Passage | King Vidor, Jack Conway, W.S. Van Dyke | Spencer Tracy, Robert Young, Walter Brennan | Adventure Drama | Nominated for Academy Award. #19 in Top Grossing Films. |
| Nutty But Nice | Jules White | The Three Stooges | Comedy Short |
Read more about this topic: List Of American Films Of 1940