"We both will benefit from an open, secure, reliable Internet. Outright theft that we are experiencing must be viewed as out of bounds and needs to stop," Biden said, while also calling for cooperation with the rising Asian power.
The United States accuses China of waging a vast hacking campaign against its government and companies, with a recent study saying that the theft of trade secrets was costing corporate America hundreds of billions of dollars a year.
Biden voiced hope that the annual Strategic and Economic Dialogue would build trust between the United States and China, saying: "Our relationship is and will continue to be a mix of competition and cooperation."
The talks involve senior officials including Secretary of State John Kerry, whose attendance had been in doubt after his wife was hospitalized with seizure-like symptoms.