Some of the threats are "absolutely" sponsored by governments, the president said. "Some are state sponsored. Some are just sponsored by criminals."
"We've made it very clear to China and some other state actors that we expect them to follow international norms and abide by international rules," Obama said, adding that Washington has already had "some pretty tough talk" with other countries.
Cyberattacks can cost billions of dollars, lead to stolen industry secrets and place the U.S. at a competitive disadvantage, he said.
Obama is scheduled to meet with a group of CEOs at the White House later in the day to solicit their input on how the government and private sector together can improve U.S. security for the Internet, online databases and more. The White House has not yet named the executives.
(Read More: A 12-Year-Old Could Hack Most Companies: Expert)
The meeting comes after U.S. authorities said they were investigating reports that the president's family had been hit by hacking.
In the interview, Obama said that he did not know whether reports were true that hackers had posted financial and personal information online about his wife, Michelle, along with other high-profile Americans.
(Read More: TransUnion: Perps Had Michelle Obama's Personal Info)
"It would not shock me if some information ... among people who presumably have pretty good safeguards against it, still gets out," he said.
Obama signed an executive order a month ago directing authorities to improve information sharing on cyberthreats. However, such orders do not carry the weight of law, and Obama told ABC that Congress has to act.
A Senate cybersecurity bill last year failed to pass and was opposed by business groups.
"There are ways that we can harden our critical infrastructure, our financial sector," Obama said. "They need to get this done."