Masatoshi Sanma (born August 18, 1977 in Naka, Tokushima) is a Japanese slalom canoeist who competed at the international level from 1997 to 2011.
He was eliminated in the semifinals of the C2 event at the 2008 Summer Olympics in Beijing, finishing in 9th place.His partner in the C2 boat was Hiroyuki Nagao.