See main article: 1840 United States presidential election.
| Election Name: | 1840 United States presidential election in Missouri |
| Country: | Missouri |
| Type: | presidential |
| Ongoing: | no |
| Previous Election: | 1836 United States presidential election in Missouri |
| Previous Year: | 1836 |
| Next Election: | 1844 United States presidential election in Missouri |
| Next Year: | 1844 |
| Election Date: | October 30 - December 2, 1840 |
| Image1: | Martin Van Buren circa 1837 crop.jpg |
| Nominee1: | Martin Van Buren |
| Party1: | Democratic Party (United States) |
| Home State1: | New York |
| Running Mate1: | none |
| Electoral Vote1: | 4 |
| Popular Vote1: | 29,969 |
| Percentage1: | 56.63% |
| Nominee2: | William Henry Harrison |
| Party2: | Whig Party (United States) |
| Home State2: | Ohio |
| Running Mate2: | John Tyler |
| Electoral Vote2: | 0 |
| Popular Vote2: | 22,954 |
| Percentage2: | 43.37% |
| Map Size: | 340px |
| President | |
| Before Election: | Martin Van Buren |
| Before Party: | Democratic Party (United States) |
| Before Color: | FF3333 |
| After Election: | William Henry Harrison |
| After Party: | Whig Party (United States) |
| After Color: | FF3333 |
The 1840 United States presidential election in Missouri took place between October 30 and December 2, 1840, as part of the 1840 United States presidential election. Voters chose four representatives, or electors to the Electoral College, who voted for President and Vice President.
Missouri voted for the Democratic candidate, Martin Van Buren, over Whig candidate William Henry Harrison. Van Buren won Missouri by a margin of 13.26%.