Coroner's spokesman Craig Harvey said the 42-year old Irabu hanged himself.
A star in Japan, Irabu's contract was purchased by the San Diego Padres in early 1997.
But Irabu didn't want to play in San Diego and the club traded him to the Yankees where he earned World Series rings in 1998 and 1999.
The Yankees traded him to Montreal after the 1999 season.
He played two seasons with the Expos and one more with the Texas Rangers before retiring in 2002.
Irabu had a few run-ins with law in recent years.
In 2008, he was accused of assaulting a bar manager in Japan after allegedly drinking 20 glasses of beer.
And just last year, he was arrested in Gardena for drunk driving.