TMZ reports that police were called to perform a "welfare check" on the star after a family member reported him missing.
Police officers later found his body at the Los Angeles River in Sunland where he lived.
Homicide detectives have confirmed that the death was a suicide.
Salling's attorney Michael Proctor has released a statement regarding Mark's passing to People magazine:
“I can confirm that Mark Salling passed away early this morning. Mark was a gentle and loving person, a person of great creativity, who was doing his best to atone for some serious mistakes and errors of judgment,” he said.
“He is survived by his mother and father, and his brother. The Salling family appreciates the support they have been receiving and asks for their privacy to be respected.”
The news comes shortly after the 35-year-old plead guilty to possession of child pornography involving a prepubescent minor in open court. Police found more than 50,000 “sexually charged” images and videos of child victims aged three to five on Salling's computers and hard drives after being tipped off by his ex-girlfriends who had seen the footage. Salling was set to receive his sentencing in March and was expected to face four to seven years in prison.
If you or someone you know needs help, you can speak confidentially to a trained counsellor 24 hours a day at headspace.org.au or Kids Helpline: 1800 55 1800.