Peter Myndert Dox (September 11, 1813 – April 2, 1891) was an American politician who served the state of Alabama in the U.S. House of Representatives between 1869 and 1873. He was born in Geneva, Ontario County, New York on September 11, 1813, and graduated from Hobart College at Geneva in 1833. He studied law, was admitted to the bar, and practiced at Geneva. Dox served as a member of the New York State Assembly in 1842, and as a judge of the Ontario County courts from November 1855 until his resignation on March 18, 1856. He then moved to Alabama and settled in Madison County, where he engaged in agricultural pursuits.
Dox was a delegate to the Alabama constitutional convention of 1865. In 1868, he was elected as a Democrat to the U.S. House of Representatives, and reelected for the following term, serving until 1873. He retired from public life, and died in Huntsville on April 2, 1891. He is buried in Maple Hill Cemetery in Huntsville.