Itaru Sakai (b. 24 March 1970, Osaka, Japan) is a Japanese composer.

He received his first piano lessons at age four and composed his first composition Carrying two years later. He was a flutist in his high school band when he composed his first composition for winds, Seventh Night of July. In 1990, he entered the Conservatory of Osaka where he studied composition with Hideki Tanaka and Kunihiko Chihara. In 1996 he received a Master of Arts in musicology from the same institution.

In 1997, his compositions were selected and interpreted in the framework of the 52nd National Sports Festival. His works include, besides many works for wind orchestra, chamber music and solo pieces.