"This is the country that invented internet," he said to Re/code co-founder Walt Mossberg at the tech-centric Code Conference on Wednesday.
"How can Americans live like this?" he asked.
The issue is crucial to the country's future, as much of America's wealth in the 20th century was based on a robust infrastructure—like highways—and high-quality broadband infrastructure will be crucial to prosperity in the 21st century,
He also noted that Comcast is his service provider.
He also acknowledged that Sprint, which be bought a majority stake in, still has many problems with its network.
"I've only owned the company for six months," he said. "It takes a few years to build."
He also said there's a good chance that Alibaba's IPO could be the biggest ever, and that eventually the company would come to the US, though probably not for many years.
Disclosure: NBCNews group is a minority stakeholder in Re/code and has a content sharing partnership with it. Comcast is NBC Universal's parent company.