John Longville (born September 21, 1949 in Saint Paul, Minnesota) is a Democratic politician who served in the California State Assembly from 1998 until he was termed out in 2004, representing part of San Bernardino County. He succeeded Joe Baca, who was elected to the State Senate, and was succeeded by Baca's son, Joe Baca, Jr. Longville previously served as mayor of Rialto from 1987 until 1998, and for seven years prior to that as a member of the Rialto city council.
In the wake of the 2000 presidential election vote-counting problems in Florida, he wrote and secured legislative adoption of Article II, Section 2.5 of the California State Constitution, mandating that all legally cast votes in California elections must be counted. The amendment was approved by the voters of California in the March 2002 state election.
In addition to his terms in the state legislature, Longville is known in Southern California as a founder of the Metrolink commuter rail system.
In September 2007, he was appointed to fill a mid-term vacancy on the board of directors of the San Bernardino Valley Water Conservation District, and was elected and reelected to that board without opposition in 2009 and 2013, continuing to serve in that position at the present time.
In November 2008, Longville was elected to the San Bernardino Community College District Board of Trustees. He was reelected in November 2012 and currently serves as president of the board.