Lahr is a surname. Notable people with the surname include:
Bert Lahr (1895–1967), born Irving Lahrheim, American actor of Jewish German descent Jane Lahr (born 1943), daughter of Bert Lahr, sister of John Lahr John Lahr (born 1941), American theater critic Charles Lahr (1885–1971), German-born Londoner anarchist, bookseller and publisher Warren Lahr (1923–1969), professional American Football player