The star has voluntarily enrolled at a treatment facility to address "substance addiction" issues, and the news sparked fears he would be cut from the cast of the musical Tv series.
However, executives behind the popular show have now spoken out to insist Monteith will remain part of the series despite his troubles.
A statement from 20th Century Fox Tv, the company behind Glee, reads, "Cory is a beloved member of the Glee family and we fully support his decision to seek treatment. Everyone at the show wishes him well and looks forward to his return."
The Glee cast is currently shooting the show's fourth season.