Bayarsaikhan is a Mongolian surname. Notable people with the surname include:
Bayanmönkhiin Gantogtokh (born 1972), Mongolian wrestler Gantogtokh Gantuya (born 1998), Mongolian footballer Ireedui Gantogtokh (born 1995), Mongolian entrepreneur, social activist and YouTuber Khandsuren Gantogtokh (born 1997), Mongolian volleyball player Tuguldur Gantogtokh (born 2005), Mongolian footballer