The current projections for future earnings put the fair market value at 18,000 for the Dow Jones Industrial Average, Wharton School professor Jeremy Siegel told CNBC on Monday.
"It doesn't mean that we're going to get there right away or we're going to get there in a straight line," Siegel said in a "Squawk Box" interview. "We've had a long time without even a 10 percent correction."
But he added: "I don't think this bull market is over yet. I still think there's good gains to come."
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In January, Siegel had predicted the Dow could hit 16,000 by year end. That happened for the first time ever when the Dow closed on Thursday. The closed above 1,800 for the first time a day later.
Premarket trading Monday morning in U.S. stock futures pointed to a higher opening on Wall Street.
Siegel pointed out: "We had an earnings gain this year over last year of about 10 to 12 percent, which is pretty good in a slow economic growth situation."
"The current projections are another 8 percent [for] next year. So it could go higher" if the economy were to speed up, he added.
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—By CNBC's Matthew J. Belvedere. Follow him on Twitter @Matt_SquawkCNBC.