Margaret Lea Houston (April 11, 1819 – December 3, 1867) was the third wife of politician Sam Houston of Texas. They married in 1840 when she was 21, during his term as a representative in the Congress of the Republic of Texas. When he was elected to a second term as the President of the Republic of Texas, in 1841 Margaret became the First Lady of the Republic of Texas. Disliking politics, for thirteen years Margaret remained in Texas while Sam Houston was in Washington, D.C.