"What can I say that hasn't been said Already. The guy with the big heart, who I had the immense pleasure of having worked with for so long, has left the building. Go on Lee, don't know how I'll ever forget you. One of the last things we laughed at was the old saying we knew so well... 'hurry up and wait,'" the Uriah Heep Facebook page said on Saturday.
The British musician joined Uriah Heep in 1971 and appeared on 17 of the band's albums. He left the group in 2007.
He also collaborated with Osbourne on the 1980s records Blizzard of Ozz, Diary of a Madman and Live EP.
"It's been 39 years since I've seen Lee but he lives for ever on the records he played on for me, Blizzard of Ozz and Diary of a Madman. Lee Kerslake RIP," Osbourne tweeted.
Kerslake had been battling cancer since 2018.