Ryuji Horii (堀井 利有司, Horii Ryuji, born November 25, 1974 in Osaka, Japan) is a retired Japanese male backstroke swimmer.

Horii is best known for winning a silver medal at the 1995 Summer Universiade in Fukuoka.

He won a bronze in the 1994 Asian games in Hiroshima, and another at the 1995 Pan Pacific championships in Atlanta.

Horii represented Japan at the 1996 Summer Olympics in Atlanta, Georgia.

This Japanese swimming biography is a stub.