Karl Manne Georg Siegbahn (December 3,1886 - September 26, 1978) was a Swedish physicist, who received the Nobel Prize in Physics in 1924 for his discoveries and research in the field of X-ray spectroscopy . He was born in Örebro, Sweden.

Karl Manne Georg Siegbahn obtained his Ph.D. at the Lund University in 1911, his thesis was titled Magnetische Feldmessungen (magnetic field measurements).

His son Kai Siegbahn received the same Nobel Prize in Physics in the year 1981.