Facebook sellers misunderstand revenue growth forecast: Munster

Analyst 'big believer' in Facebook's virtual reality theme

Facebook's warning that it expects its growth to slow later this year has spooked investors, but they may be overreacting, analyst Gene Munster said Thursday.

Facebook CFO David Wehner said during Facebook's conference call Wednesday that ad revenue growth will likely decelerate in coming quarters. But Piper Jaffray's Munster told CNBC Wall Street had already accounted for growth of 40 percent and 38 percent in the third and fourth quarters, respectively.

The social media giant reported revenue growth of 43 percent in the second quarter.

Read MoreFacebook quarterly results beat on most metrics

"I think [Wehner] was just trying to temper some expectations," Munster said in a "Squawk Box" interview.

Facebook on Wednesday reported adjusted second-quarter earnings of 50 cents per share on $4.04 billion in revenue, compared with Wall Street expectations of 47 cents per share on $3.99 billion.

Despite the earnings beat, share prices were down nearly 4 percent Thursday. (Click here for the latest price.)

Munster said investors should not expect Facebook to quickly ramp up revenue from its Instagram photo-sharing business and its messaging apps. The company will likely focus on making money from Instagram next year and possibly do the same with Facebook Messenger and WhatsApp in 2017 or beyond, he said.

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Investors were also seen reacting to higher costs. Facebook's expenses in total came in at $2.77 billion, up 82 percent from the same period last year.

Mark Mahaney, lead Internet analyst at RBC Capital Markets, said Thursday that Facebook has so far managed its investments wisely.

"This is still early stage for Facebook. The bigger mistake would be under-investing, not over-investing," he told "Squawk on the Street." "Unlike Google, they seem to be better at guiding to and then meeting or beating those expense goals."

While Mahaney said he expects a "pretty solid deceleration" in Facebook's growth rate, that deceleration will also be consistent and moderate.

"If that's what happens you're going to have close to $4 in earnings in 2017, and the stock's going to go higher. We may retrace shortly here, but overall fundamentals are about as strong as you can find in the sector and the valuation is still reasonable."

FB Q2 result 'good news all around': Analyst

James Cakmak, analyst at Monness, Crespi, Hardt & Co., told "Squawk Box" that investors should focus on Facebook's 50 percent constant currency revenue growth and 55 percent foreign-exchange-neutral advertising gain.

"No other company in the ad space is posting these kinds of growth off of this kind of base," he said.

The company said it saw monthly active users (MAUs) of 1.49 billion for June, with 1.31 billion MAUs on mobile. Mobile advertising revenue represented about 76 percent of its total ad revenue for the quarter.

"They have more growth levers than I think any other company in the Internet space aside from Amazon," Cakmak said. "They're going after Twitter with real-time [content]. They're going after YouTube with video. They're going after commerce ... so the sky's the limit."

—CNBC's Everett Rosenfeld contributed to this story.

Disclosure: Gene Munster and James Cakmark do not own shares of Facebook, nor do their families. Mark Mahaney's family owns the stock. None of the analysts' firms own greater than a 1 percent share of the stock, and they do not provide investment banking services to Facebook.