The Ligier JS25 was a Formula One car designed by Michel Beaujon and Claude Galopin for use by the Ligier team during the 1985 Formula One season. Like its predecessor, the JS23, the JS25 was powered by a turbocharged Renault V6 engine although the car ran on Pirelli instead of Michelin tyres after the French company pulled out of Grand Prix racing at the end of 1984. Drivers of the car were initially their 1984 driver Andrea de Cesaris and veteran Jacques Laffite who returned to the team after two fruitless years at Williams, but after a series of crashes, de Cesaris was fired by team boss Guy Ligier and replaced by Philippe Streiff.