Bieber, 22, took to Instagram with a sweet message for Odom, reported Hollywood Life.
"We all believe in you! Praying for you Lamar," Bieber captioned his Instagram, a joyous picture of Odom beaming on the basketball court back when he played for the Lakers.
The 35-year-old basketball star recently regained consciousness after collapsing at a brothel in Nevada earlier this week and Bieber is the latest star to take to social media to reach out to Odom.
He has received so many cards, balloons and cool presents that it is "beginning to look like Christmas" in his room.
Odom's estranged wife Khloe, 31, has been with him since he was admitted to hospital and has barely left his side.