Woods, who has won 14 times in the Majors, has been struggling with form and fitness recently, but Nicklaus believes that the world number one still has enough time to set a new record.
"I feel very bad for Tiger. He's really worked towards my record," Nicklaus told ESPN Radio. "I still think he'll break my record.
"As long as he is physically is able to do it. He's 38 years old and he's probably got another 10 years at least of being able to compete - that's 40 more Majors to win five of them. It shouldn't be too difficult.
"But then again, I've always said he's just got to do it."
Woods will miss this week's Masters tournament after requiring surgery on his back last month.