Chinese Foreign Ministry spokesman Qin Gang stressed his country remained "opposed" to Google's conclusions about last month's attack, which targeted U.S. businesses' trade secrets, human-rights workers in China and the search-engine giant itself.
"Reports that these attacks came from Chinese schools are totally groundless and the accusation of Chinese government involvement is also irresponsible and driven by ulterior motives," the Chinese spokesman said.
Beijing also rebuked allegations on Tuesday that the attacks — which began in 2008 — stemmed from two schools in China, one of which is said to have close ties to the military.
Google's problems in China have added to tensions between the U.S. and China on a range of economic and national security issues. Secretary of State Hillary Rodham Clinton has called on China to probe the attack. U.S. officials have discussed the issue with their Chinese counterparts, and Clinton has said that Internet freedom is a diplomatic priority for the Obama administration.
China's latest reproach signals the rate at which Beijing leaders and Google are growing further apart.
In the immediate aftermath of the attack, Google threatened to cease doing business in the country, though it has not yet decided on that course of action. It also said it would stop censoring the results of Internet searches, a decision criticized by China but cheered by members of Congress.