Lea Michele's message for Cory Monteith on what would have been his 33rd birthday.

Cory Monteith would have turned 33 years old yesterday, and to commemorate his birthday, Monteith’s Glee co-star and girlfriend Lea Michele posted a sweet picture of her late love.

“I know you’re serenading everyone right now.. We love you Cory! Happy Birthday..” Michele, 28, wrote.

Monteith died in July 2013 following an accidental heroin and alcohol overdose in a Vancouver hotel room.

The couple had been seeing each other for more than a year when Monteith died.

Michele also marked the date last year, with a sweet picture of the two of them laughing together.

Glee ended earlier this year after six seasons. One episode of the fifth season honoured Monteith with an episode called The Quarterback.

Michele is now dating Matthew Paetz.

Read more on Glee alumni

Lea Michele: I’ve lost two people.

First photos of Glee’s transgender character, post transition.

Glee co-stars pay tribute to Corey Monteith.