Lambton—Kent—Middlesex (formerly known as Middlesex—Kent—Lambton) is a federal electoral district in Ontario, Canada, that has been represented in the House of Commons of Canada since 1997. The district includes all of Middlesex County except the City of London and Thames Centre Township, all of the Municipality of Chatham-Kent north of the Thames River, and excluding the former City of Chatham, and the Municipalities of Lambton Shores, Brooke-Alvinston Township, Dawn Euphemia Township, Warwick Township and the Indian reserves of Kettle Point and Walpole Island in the County of Lambton. The population in 2001 was 105,291, and the area is 5,277 km².