Hewlett-Packard remains a company "under assault," argued hedge fund short-seller Jim Chanos Thursday, saying that's why he's still betting against CEO Meg Whitman's turnaround of the tech giant.
"Whitman seems to be a lot more optimistic than we are," Chanos, founder and president of Kynikos Associates, said on CNBC's "Squawk Box." His hedge fund has $5 billion in assets of management.
(Read more: Chanos on why stocks seem tobe signaling a debt deal ...)
HP, which was kicked out of the Dow Jones Industrial Average last month, saw its stock increase nine percent Wednesday, after she expects the year-over-year revenue decline in fiscal 2014 to moderate with "pockets of growth" before business accelerates again in 2015.
Chanos read her comments differently: "They are now talking about revenue declines in 2014. That's not what they were saying before. In effect, the guidance keeps coming down at that company."
(Read more: HP sees revenue stabilizing in 2014, growth in 2015)
"They're talking about lots of restructuring. They're talking about margins improving. I'm just hard-pressed to see how margins are going to improve in any of their businesses given the secular headwinds that are going on," he explained.
A new report from research firm Gartner underscored Chanos's point. Global personal computer shipments tanked almost nine percent during the third quarter—a period of historically strong demand—to the lowest level in five years.
"They have a lot of different businesses. They have enterprise, printing, and PCs. But all of these businesses are declining right now. That's the problem. They're all under assault," Chanos said.
"Turning around tech companies—IBM in the early '90s notwithstanding—is a very difficult undertaking," he continued. "Maybe she can do it. We'll see."
At the 2012 CNBC-Institutional Investor Delivering Alpha Conference, Chanos touted his dim view on HP and talked about his short position on the stock—calling it "the ultimate value trap."
Apple and Samsung longs
For the same reasons Chanos has been short HP, he said he's long Apple and Samsung. It's because the popularity of mobile devices is the major factor in declining PC sales, which he expects to "accelerate on the downside."
"[Samsung] is outright, outright very, very cheap," Chanos added. "It's got very great returns on capital. It invests and expenses [in R&D]—unlike a lot of guys like Hewlett and others who go out and acquire their R&D, which has been one of our big complaints. Samsung actually does it homegrown. As does Apple basically."
But he said he cautions people "when they look at our SEC filings understand our longs are generally offset by things we're short."
Another long, and a mystery short
Another long play Chanos talked about Thursday: "Workday versus one of the cloud shorts."
"The wonderful thing about the short side is I don't always have to disclose what I'm short," he continued. "We have a fun one we're short that's just an accounting nightmare. We'll leave it at that."
—By CNBC's Matthew J. Belvedere and Maneet Ahuja. Follow them on Twitter at @Matt_SquawkCNBC and @WallStManeet respectively.