- The stock market is feeling pressure from concerns around the coronavirus, but that's not a bad thing, Wharton School professor Jeremy Siegel said.
- "I actually welcome a little bit of this pullback," Siegel told CNBC.
- Siegel has been warning for weeks that the stock market was fully valued.
"I actually welcome a little bit of this pullback," Siegel said on "Closing Bell." "It's good to get ... a reality check. There was really nothing going on that could keep on forcing that market up at that level."
Siegel's comments come just after the bell Monday, a day in which the three major indexes closed solidly in the red as concerns swelled around the coronavirus in China. At least 2,900 cases are confirmed worldwide, and the death toll in China, where the majority of cases have been reported, is at least 82.
U.S. health officials said Monday they're monitoring the condition of more than 100 people across 26 states, including five people who contracted the virus in China and returned to the U.S.
The Dow Jones Industrial Average fell 1.6% in its worst trading day since October, while the S&P 500 also dropped 1.6% to snap a 74-session streak without a 1% decline. The Nasdaq Composite's decline of 1.9% is its largest since August.
Investors began showing signs of worry regarding the coronavirus last week, with stocks posting their first weekly declines of the still-new year.
The market had kicked off 2020 on a strong footing, building on a 2019 in which the S&P 500 posted its best annual gains since 2013.
Siegel, however, had been warning that stocks' continued move to the upside was the result of a "momentum-driven market." He recently reiterated his concerns that the market was "going up a little too far, too fast."
"Once you go too fast, a little stone can throw you off," the professor said on CNBC's "Trading Nation" on Jan. 17.
On Monday, Siegel said the situation with the coronavirus was the kind of development to which he was alluding.
"So in a way, I think this is a healthy check," said Siegel, author of the popular investment strategy book, "Stocks for the Long Run."
"Now can we get back on that train? Yes," he continued. "Sometimes a little pause and then people get their confidence back ... and then we're back on that train. We'll have to see at this particular juncture."
But even with the recent pullback, Siegel said stocks remain fully valued. He pointed to the S&P 500 trading around 19 to 20 times this year's earnings, which he said is higher than the post-World War II average of roughly 17.
"I didn't see what was really driving the market straight up in early January except relief that the worst of the trade wars [with China] was over the hump," Siegel said. "When you're priced like this, any little stone in the way, such as the coronavirus, you're going to get a stumble."
— CNBC's Fred Imbert contributed to this report.