Billboard reported that the singer had struggled with addictions to drugs and alcohol at various points in his life. He spoke about those addictions in a 2009 interview with Noisecreep.
Linkin Park is well known for hits like 2000's "In the End" and 2003's "Numb," the latter of which led to a collaborative EP with Jay-Z called "Collision Course."
Bennington had been on a world tour with Linkin Park in support of their latest album, "One More Light." A close friend of late Soundgarden singer Chris Cornell, Bennington performed Lenord Cohen's "Halleliujah" at his funeral in May. Cornell died of a suicide by hanging May 17.
Bennington is survived by his wife, Talinda Ann Bentley, and six children.