Daiki Nishiyama (?? ??, Nishiyama Daiki, born November 20, 1990 in Higashihiroshima, Hiroshima) is a Japanese judoka.
He won the silver medal in the middleweight (90 kg) division at the 2010 World Judo Championships.
His big throws are o soto gari, o uchi gari, sode tsurikomi goshi and te guruma.
He is currently ranked number two in the -90 kg weight division behind Illias Iliadis.
Because of nishiyamas ranking and recent form it has come as even more of a surprise that he was not includeded in the Japan squad for the 2012 olympics.
The Japanese judo association instead went with the more experienced masaeshi nishiyamam in the -90 kg category.