The London Fringe Theatre Festival is a Canadian annual fringe theatre and related arts festival in London, Ontario. It is credited with triggering a resurgence in local playwriting^[1] and performance after the University of Western Ontario cancelled its drama program.

The first festival was presented in 2000,^[2] comprising 28 local, national, and international productions over a ten-day schedule. Prior to 2009 it began on the province's Civic holiday weekend, but was moved to the beginning of June to take advantage of the east-to-west circuit of the Canadian Association of Fringe Festivals. By 2019, under the direction of executive producer and co-founder Kathy Navackas, the festival had grown to host over 50 productions and workshops.^[3]

The London Fringe Festival organization also sponsored and supported theatre- and arts-related events throughout the year, including a Nuit Blanche event and The Lost Soul Stroll, a historical ghost tour.

In 2020 the organization joined with London Community Players to form the Palace Theatre Arts Commons.^[4] After dismissing Navackas and its other staff,^[5] the Palace Theatre presented a small "Fringe Binge" festival in September 2021 featuring only three productions, chosen from local companies, and four curated musical acts.^[6]