The 2011 Japanese motorcycle Grand Prix was the fifteenth round of the 2011 Grand Prix motorcycle racing season. It took place on the weekend of 29 September–2 October 2011 at the Twin Ring Motegi, located in Motegi, Japan. The Grand Prix, originally scheduled for 24 April, was moved to 2 October due to the effects of the Tōhoku earthquake and the Fukushima I nuclear accidents.