Walter Lowrie (December 10, 1784-December 14, 1868) was a teacher, farmer, and politician from Butler County, Pennsylvania. He served in both houses in the state legislature and represented Pennsylvania in the United States Senate.
After his term as a Senator, Lowrie stayed on as Secretary of the Senate for eleven years. In 1836 he moved to New York City and went to work with the Missionary Board of the Presbyterian Church. He remained with them until his death. Several of his sons had became clergymen, and two entered the foreign missions. A nephew, Walter H. Lowrie, later served as chief justice of Pennsylvania's Supreme Court.
Lowrie died in New York City in 1868 and is interred in the First Presbyterian Church in Manhattan.